What are the must-see attractions at Lake Kawaguchi, Japan?

Mount Fuji, of course, is the star attraction, offering breathtaking views from various points around the lake. The Kawaguchiko Music Forest Museum is a lovely spot for a relaxing afternoon, with its beautiful gardens and collection of musical instruments. For something a bit different, check out the Itchiku Kubota Art Museum, showcasing stunning kimono art. And don't forget the Kawaguchiko Natural Living Center, which provides insights into the local flora and fauna.

What are the best accommodations in Lake Kawaguchi?

Among the accommodations in Lake Kawaguchi, Traditional Experience With Best Fuji View Aoiso , Lake Villa Kawaguchiko and Mizno Hotel are the most popular ones.

Are there any seasonal events or cultural festivals at Lake Kawaguchi, Japan?

Lake Kawaguchi hosts several events throughout the year. The Fuji Shibazakura Festival in spring is famous for its stunning display of pink moss phlox. In autumn, the autumn leaves provide incredible colours, making for picturesque walks and hikes. The area also celebrates various local festivals throughout the year, often linked to the harvest or local shrines; checking local listings closer to your travel dates would be advisable.

What are the best accommodations with a pool in Lake Kawaguchi?

Mizno Hotel , Kaze No Terrace Kukuna Hotel and Hotel New Century are the best accommodations with a pool in Lake Kawaguchi.

What are the most characteristic landscapes and terrains found at Lake Kawaguchi, Japan?

The dramatic backdrop of Mount Fuji is undeniably the most striking feature. The lake itself is surrounded by hills and mountains, offering a variety of scenic viewpoints. You'll find areas with lush forests, volcanic rock formations, and beautiful cherry blossom trees (depending on the season). The area's diverse terrain makes it suitable for many outdoor activities.

What are the best accommodations with a jacuzzi in Lake Kawaguchi?

The best accommodations with a jacuzzi in Lake Kawaguchi are Traditional Experience With Best Fuji View Aoiso , Lake Villa Kawaguchiko and Mizno Hotel .

What are the best outdoor activities at Lake Kawaguchi, Japan?

Hiking trails abound, offering varying levels of difficulty, with stunning views of Mount Fuji. Boat tours on the lake provide a different perspective of the scenery. Cycling around the lake is also popular, offering a leisurely way to explore. In winter, there are opportunities for snow activities, depending on snowfall.

What are the best accommodations for families and kids in Lake Kawaguchi?

The best accommodations for families and kids in Lake Kawaguchi are Lake Villa Kawaguchiko , Mizno Hotel and Villa Ensoleille .

What is the best time of year to visit Lake Kawaguchi, Japan with kids?

Spring and autumn are generally considered ideal for families. Spring offers pleasant weather and the Fuji Shibazakura Festival. Autumn provides beautiful colours and comfortable temperatures. Summer can be hot and humid, while winter can be quite cold, although snow activities might appeal to older children.

What are the best pet friendly accommodations in Lake Kawaguchi?

The best pet friendly accommodations in Lake Kawaguchi are Lake Villa Kawaguchiko , Mizno Hotel and Kawaguchiko Country Cottage Ban .

Are there any local customs to be aware of at Lake Kawaguchi, Japan?

As with anywhere in Japan, politeness and respect are highly valued. Removing shoes before entering homes or some traditional establishments is customary. Quiet conversation in public spaces is appreciated. Familiarise yourself with basic Japanese phrases; even a simple 'hello' and 'thank you' will be well received.

What are the best accommodations with parking in Lake Kawaguchi?

Traditional Experience With Best Fuji View Aoiso , Lake Villa Kawaguchiko and Mizno Hotel are the best accommodations with parking in Lake Kawaguchi.

What are the best ways to interact with locals and learn about their culture at Lake Kawaguchi, Japan?

Visiting local shops and restaurants is a great way to engage with the community. Many establishments are family-run, offering opportunities for friendly interactions. Participating in local festivals, if any are on during your visit, provides a wonderful insight into the local culture. Consider taking a Japanese language class before your trip.

What are some lesser-known attractions or hidden gems at Lake Kawaguchi, Japan?

The Saiko Iyashi no Sato Nenba is a charming traditional village, offering a glimpse into rural life. The Aokigahara Forest, while known, is often overlooked for its beauty and hiking trails (exercise caution and stick to marked paths). Some of the smaller temples and shrines dotted around the lake offer moments of peace and quiet reflection.

What are some must-try local dishes at Lake Kawaguchi, Japan?

Local restaurants offer a variety of dishes featuring fresh, seasonal ingredients. Try the *hojicha* (roasted green tea) ice cream, a regional specialty. Many restaurants offer variations of *yaki soba* or *udon* noodles. Local fish from the lake is also a popular choice; check out the local restaurants for their daily specials.

Lake Kawaguchi Places to Stay and Lodgings

9.1 63 reviews

富士旅の家

house, Fujikawaguchiko Town

富士旅の家, located in Fujikawaguchiko Town, is a 16-minute walk from Fuji-Q Highland and within a few kilometres of Lake Kawaguchi and the Mount Kachi Kachi Ropeway.
This 88-square-metre holiday home sleeps up to 11 guests, offering two bedrooms, a bathroom, a well-equipped kitchen, free Wi-Fi, and a terrace with mountain views, plus access to shared amenities including a lounge and laundry service.

9.5 553 reviews

Cottage Pastorale

house, Fujikawaguchiko Town

Cottage Pastorale is located just 3 km from Lake Kawaguchi, offering stunning views of Mount Fuji, which is 18 km away. The property has received excellent ratings for location, cleanliness, and user satisfaction.
The accommodation features comfortable units with flat-screen TVs, fully equipped kitchens, and private bathrooms. Guests can enjoy free Wi-Fi, air conditioning, on-site parking, barbecue facilities, and a free shuttle service to explore the surrounding area.

9.8 356 reviews

Fuji Kawaguchiko/5 Mins To Train Station/tohaku站前

apartment, Fujikawaguchiko Town

This self-catering train near Fujikawaguchiko Town, Yamanashi Prefecture, offers convenient access to the area's attractions, although precise distances aren't specified.
Sleeping up to six guests, this three-bedroom railcar boasts a kitchenette with fridge, freezer, and microwave, plus air conditioning, a garden, parking, and excellent guest ratings.

10 125 reviews

絶景！屋上付き全室富士山が望める一軒家最大7名宿泊可能

apartment, Fujikawaguchiko Town

This Fujikawaguchiko Town apartment, a 3-minute drive from a supermarket and 5 minutes from the Fuji-Q Highland/Kawaguchiko Interchange, offers uninterrupted Mount Fuji views and is within a 30-40 minute walk of Kawaguchiko Station.
Sleeping up to six guests in two bedrooms and one bathroom, this self-catering property boasts a rooftop terrace with stunning Mount Fuji views, on-site parking, and a fully equipped kitchen including a fridge and freezer; passport details are required for foreign guests.

8.7 37 reviews

富士山下Cottage-a

house, Narusawa Village

富士山下 Cottage-A is a self-catering property in Narusawa Village, Yamanashi Prefecture, conveniently located 6.4km from Lake Kawaguchi and 7.2km from Fuji-Q Highland amusement park, offering stunning views of Mount Fuji (27km away).
This 60 square metre house features one bedroom, one bathroom, and can accommodate up to six guests, boasting a fully equipped kitchenette, air conditioning, a terrace, private parking, and excellent cleanliness ratings.

8.7 751 reviews

Fuji Scenic House 73

apartment, Fujikawaguchiko Town

This apartment is located in Fujikawaguchiko Town, a short walk from Kawaguchiko Station and just 9.9 miles from Mount Fuji, offering easy access to both buses and trains. It has received very good ratings for cleanliness and user experience, and an excellent rating for its location.
The apartment features a fully equipped kitchen with a microwave, fridge, and stovetop, allowing you to prepare your own meals. It also offers a range of amenities including air conditioning, free Wi-Fi, a terrace or balcony, and parking.

9.2 8 reviews

Habitacion Towa

apartment, Fujikawaguchiko Town

This flat in Fujikawaguchiko Town offers complimentary Wi-Fi and free on-site parking, with laundry services available for guest convenience.
Spanning 48 square meters, this apartment features a kitchen equipped with a fridge, freezer, and microwave, air conditioning, and a garden, providing a comfortable base for exploring the area.

9.8 479 reviews

Enjoy Mt. Fuji And Lake Kawaguchi On The Roof! No Smoking!

house, Fujikawaguchiko Town

This stylish new house in Fujikawaguchiko Town enjoys a prime location, a mere 0.4km walk from both Kawaguchiko Station and Lake Kawaguchiko.
Sleeping up to six guests in two bedrooms and one bathroom, the property boasts a fully equipped kitchen, laundry facilities, a rooftop terrace with Mount Fuji and lake views, and free parking for two cars.

10 91 reviews

Newwabi-sabi Historic Home - Walk To The Lake

apartment, Fujikawaguchiko Town

This historic Taishō-era farmhouse, offering a unique blend of traditional Japanese and anime-inspired design, is located near Lake Kawaguchiko, providing views of Mt. Fuji and convenient access to Fujikawaguchiko Town.
This 1-bedroom, 1-bathroom dwelling accommodates up to 8 guests and features a private garden, parking, air conditioning, and a kitchen with a fridge and microwave, alongside the provision of free bicycles for local exploration.

9.9 68 reviews

河口湖駅から徒歩7分/神蔵/kagura

apartment, Fujikawaguchiko Town

This private house is situated a 7-minute walk from Kawaguchiko Station in a quiet residential district of Fujikawaguchiko Town.
This two-storey property accommodates up to six guests, offering private access to the entire dwelling including a kitchen equipped with a fridge and microwave, air conditioning, and internet, with designated parking available.

9.0 61 reviews

Tsukimisou Guest House

apartment, Fujikawaguchiko Town

This flat in Tsuru is located 2 kilometres from Fuji-Q Highland and 2.9 kilometres from Lake Kawaguchi, with Lake Kawaguchi Ohashi Bridge 2.1 kilometres away, and sits within a geothermal area offering hot spring access.
This one-bedroom apartment accommodates up to three guests, featuring air conditioning, a fully equipped kitchen, free Wi-Fi, and private parking, with Fujiomuro Sengen Shrine 3.1 kilometres and Mount Fuji 22.5 kilometres distant.

9.7 195 reviews

Classic Japan Living Kawamuraya

house, Fujikawaguchiko Town

This house is located in Fujikawaguchiko Town, a short distance from Lake Kawaguchi and Fuji-Q Highland, offering easy access to popular tourist destinations. The property has received excellent ratings for cleanliness, location and overall user experience.
The house has two bedrooms and one bathroom, covering 78 square metres. The property offers a range of amenities, including a fully equipped kitchen, a private terrace, free parking, and Wi-Fi, ensuring a comfortable and enjoyable stay.

Best family friendly Lake Kawaguchi lodging

Among the 421 accommodations in Lake Kawaguchi, here are the 4 best for families

8.6 203 reviews

Minamitsuru-gun - House - Vacation Stay 82499

house, Fujikawaguchiko Town

This holiday home is situated in Fujikawaguchiko, just 2.5 miles from Lake Kawaguchi and 14 miles from Mount Fuji, providing easy access to popular attractions. The property has received very good ratings for location, cleanliness, and overall user experience.
The accommodation offers a comfortable and well-equipped space with a fully equipped kitchen, a washing machine, and a relaxing bathroom with a bath and shower. Guests can enjoy amenities like air conditioning, free Wi-Fi, private parking, and a jacuzzi, making it ideal for a relaxing and enjoyable stay.

8.8 4461 reviews

Hotel Koryu

ryokan, Fujikawaguchiko Town

Hotel Koryu is situated on the shores of Lake Kawaguchiko, a short drive from Kawaguchiko Station and Fujikyu Highland amusement park, offering stunning views of Mount Fuji. This highly-rated ryokan is popular for its cleanliness, location, and overall experience.
The accommodation offers both traditional Japanese-style rooms and Western-style rooms, providing guests with a choice to suit their preferences. Guests can enjoy amenities like hot springs, a swimming pool, a spa, a restaurant, and a fitness centre, ensuring a relaxing and enjoyable stay.

8.6 68 reviews

ヴィラ山間堂Premier Garden Villa Bbq Bonfire Fuji View Annovillas Sankando

house, Fujikawaguchiko Town

Annovillas Sankando's Premier Garden Villa, situated in Fujikawaguchiko Town, offers stunning Fuji views and is conveniently located 2.9km from Lake Kawaguchi and 3.1km from Fuji-Q Highland.
This 165 square metre property boasts three bedrooms, one bathroom with a jacuzzi and walk-in shower, a fully equipped kitchen, and can comfortably accommodate up to 23 guests, featuring a terrace, garden, and free parking; hot springs are nearby.

9.8 41 reviews

Fujihare Lakeside Villas A Station Restaurant Walk

house, Fujikawaguchiko Town

Fujihare Lakeside Villas offers a newly constructed holiday home in Fujikawaguchiko Town, boasting prime lakeside positioning with direct views of Kawaguchi Lake and Mount Fuji, just 800 metres from premier Mount Fuji viewing points and the Funatsuhama event venue. This modern villa accommodates up to eight guests with two bedrooms and one bathroom, featuring a fully equipped kitchen, air conditioning, a jacuzzi, and on-site parking, with convenient access to public transport including the Azagawa bus stop a minute away and Kawaguchiko Station a 15-minute walk.

Best Lake Kawaguchi accommodations with a fireplace

8.4 10 reviews

湖畔を一望するプライベートホテル / The [] Time Fuji

house, Fujikawaguchiko Town

THE [] TIME FUJI is a private hotel in Fujikawaguchiko Town offering lake views, with free Wi-Fi and on-site parking.
This 100 square metre accommodation provides a fridge, microwave, air conditioning, a jacuzzi, terrace, sauna, and a user rating of very good.

10 1 review

奥富士レイクサイド

house, Fujikawaguchiko Town

This spacious five-bedroom villa is situated in Fujikawaguchiko, offering convenient access to Lake Kawaguchi, located 4.5 kilometres away, and Fuji-Q Highland, 7.9 kilometres distant.
This expansive property boasts a floor area of 592 square metres, accommodating up to 39 guests with amenities including a fridge, microwave, air conditioning, jacuzzi, sauna, spa, terrace, garden, and private parking, alongside on-site entertainment such as billiards and darts.

9.4 249 reviews

『Leaf河口湖』富士山が素晴らしい景色のプライベートガーデン

house, Narusawa Village

This spacious house is located in Narusawa Mura, at the foot of Mount Fuji, a short drive from Fuji-Q Highland and offering stunning views of the mountain. The property has received excellent ratings for its location, cleanliness, and overall experience.
The house offers a large interior with two bedrooms and one bathroom, accommodating up to 16 guests. It includes a private garden, a fully equipped kitchen, a jacuzzi, and a BBQ area, allowing for both indoor and outdoor activities.

9.7 286 reviews

Fuji Fabric Stay

house, Fujikawaguchiko Town

This house is situated in Fujikawaguchiko Town, a peaceful neighbourhood just 1.9 miles from Fuji-Q Highland and 3.2 miles from Lake Kawaguchi, offering easy access to attractions. The property enjoys excellent user, location and cleanliness ratings, ensuring a comfortable and enjoyable stay.
The accommodation features two bedrooms and one bathroom, spanning 92 square metres and comfortably sleeping up to six guests. The house offers a range of amenities including a fully equipped kitchen, a private balcony, free parking and Wi-Fi, allowing you to relax, explore and stay connected during your trip.

Frequently asked questions about accommodations in Lake Kawaguchi

What are the must-see attractions at Lake Kawaguchi, Japan?
Mount Fuji, of course, is the star attraction, offering breathtaking views from various points around the lake. The Kawaguchiko Music Forest Museum is a lovely spot for a relaxing afternoon, with its beautiful gardens and collection of musical instruments. For something a bit different, check out the Itchiku Kubota Art Museum, showcasing stunning kimono art. And don't forget the Kawaguchiko Natural Living Center, which provides insights into the local flora and fauna.
What are the best accommodations in Lake Kawaguchi?
Among the accommodations in Lake Kawaguchi, Traditional Experience With Best Fuji View Aoiso, Lake Villa Kawaguchiko and Mizno Hotel are the most popular ones.
Are there any seasonal events or cultural festivals at Lake Kawaguchi, Japan?
Lake Kawaguchi hosts several events throughout the year. The Fuji Shibazakura Festival in spring is famous for its stunning display of pink moss phlox. In autumn, the autumn leaves provide incredible colours, making for picturesque walks and hikes. The area also celebrates various local festivals throughout the year, often linked to the harvest or local shrines; checking local listings closer to your travel dates would be advisable.
What are the best accommodations with a pool in Lake Kawaguchi?
Mizno Hotel, Kaze No Terrace Kukuna Hotel and Hotel New Century are the best accommodations with a pool in Lake Kawaguchi.
What are the most characteristic landscapes and terrains found at Lake Kawaguchi, Japan?
The dramatic backdrop of Mount Fuji is undeniably the most striking feature. The lake itself is surrounded by hills and mountains, offering a variety of scenic viewpoints. You'll find areas with lush forests, volcanic rock formations, and beautiful cherry blossom trees (depending on the season). The area's diverse terrain makes it suitable for many outdoor activities.
What are the best accommodations with a jacuzzi in Lake Kawaguchi?
The best accommodations with a jacuzzi in Lake Kawaguchi are Traditional Experience With Best Fuji View Aoiso, Lake Villa Kawaguchiko and Mizno Hotel.
What are the best outdoor activities at Lake Kawaguchi, Japan?
Hiking trails abound, offering varying levels of difficulty, with stunning views of Mount Fuji. Boat tours on the lake provide a different perspective of the scenery. Cycling around the lake is also popular, offering a leisurely way to explore. In winter, there are opportunities for snow activities, depending on snowfall.
What are the best accommodations for families and kids in Lake Kawaguchi?
The best accommodations for families and kids in Lake Kawaguchi are Lake Villa Kawaguchiko, Mizno Hotel and Villa Ensoleille.
What is the best time of year to visit Lake Kawaguchi, Japan with kids?
Spring and autumn are generally considered ideal for families. Spring offers pleasant weather and the Fuji Shibazakura Festival. Autumn provides beautiful colours and comfortable temperatures. Summer can be hot and humid, while winter can be quite cold, although snow activities might appeal to older children.
What are the best pet friendly accommodations in Lake Kawaguchi?
The best pet friendly accommodations in Lake Kawaguchi are Lake Villa Kawaguchiko, Mizno Hotel and Kawaguchiko Country Cottage Ban.
Are there any local customs to be aware of at Lake Kawaguchi, Japan?
As with anywhere in Japan, politeness and respect are highly valued. Removing shoes before entering homes or some traditional establishments is customary. Quiet conversation in public spaces is appreciated. Familiarise yourself with basic Japanese phrases; even a simple 'hello' and 'thank you' will be well received.
What are the best accommodations with parking in Lake Kawaguchi?
Traditional Experience With Best Fuji View Aoiso, Lake Villa Kawaguchiko and Mizno Hotel are the best accommodations with parking in Lake Kawaguchi.
What are the best ways to interact with locals and learn about their culture at Lake Kawaguchi, Japan?
Visiting local shops and restaurants is a great way to engage with the community. Many establishments are family-run, offering opportunities for friendly interactions. Participating in local festivals, if any are on during your visit, provides a wonderful insight into the local culture. Consider taking a Japanese language class before your trip.
What are some lesser-known attractions or hidden gems at Lake Kawaguchi, Japan?
The Saiko Iyashi no Sato Nenba is a charming traditional village, offering a glimpse into rural life. The Aokigahara Forest, while known, is often overlooked for its beauty and hiking trails (exercise caution and stick to marked paths). Some of the smaller temples and shrines dotted around the lake offer moments of peace and quiet reflection.
What are some must-try local dishes at Lake Kawaguchi, Japan?
Local restaurants offer a variety of dishes featuring fresh, seasonal ingredients. Try the *hojicha* (roasted green tea) ice cream, a regional specialty. Many restaurants offer variations of *yaki soba* or *udon* noodles. Local fish from the lake is also a popular choice; check out the local restaurants for their daily specials.

Nearby regions

Best Lake Kawaguchi accommodations with a balcony

9.0 697 reviews

Akaishi Ryokan

ryokan, Fujikawaguchiko Town

Akaishi Ryokan is a traditional Japanese inn situated near Lake Kawaguchi, just a 5-minute drive from Kawaguchi Train Station, making it easily accessible to popular attractions like Kawaguchi Sengen Shrine and Fujikyu Highland Amusement Park. The ryokan enjoys a very good user rating, with guests praising its prime location, cleanliness, and friendly service.
The inn features authentic Japanese-style rooms with tatami flooring and futon bedding, offering a traditional experience. Guests can enjoy relaxing in the public hot springs, benefit from modern amenities like air conditioning and Wi-Fi, and take advantage of services like luggage storage and drink vending machines.

9.6 27 reviews

61 Fuji Petel Un -アン-

house, Fujikawaguchiko Town

This Fujikawaguchiko villa is located 1.6km from Lake Kawaguchi, a short walk from the Kawaguchiko Ohashi Bridge, and close to Mount Kachi Kachi Ropeway and Fujiomuro Sengen Shrine.
The 103 square metre property boasts one bedroom, one bathroom, sleeps eleven guests, and includes a fully equipped kitchen, jacuzzi, terrace, garden, parking, and Wi-Fi.

9.0 6338 reviews

Fuji Gran Villa - Toki -

house, Fuji-yoshida Shi

Fuji Gran Villa - Toki - is situated in Fujiyoshida, just a short walk from Fuji-Q Highland, a popular amusement park, and a short drive from Lake Kawaguchi and Mount Fuji. The hotel is a 4-star establishment with excellent user ratings for its cleanliness and location.
The hotel offers a range of modern amenities, including a swimming pool, jacuzzi, spa, and tennis court, as well as a restaurant, bar, and room service. Guests can enjoy stunning views of Mount Fuji from their rooms, relax in the garden or on the terrace, and take advantage of the hotel's shuttle service.

9.2 8 reviews

スマートコテージアイアンネスト

apartment, Fujikawaguchiko Town

The "スマートコテージアイアンネスト" apartment is situated in Fujikawaguchiko Town, just 8.6 km from Lake Kawaguchi and 11 km from Fuji-Q Highland, offering easy access to some of the region's most popular attractions.
This one-bedroom apartment, spanning 27 square metres, comfortably accommodates up to four guests and boasts a range of amenities including a fully equipped kitchen, a private hot tub, and a terrace with mountain views.

Best Lake Kawaguchi accommodations with a kitchen

9.8 72 reviews

72 Mt.view -B-　Free Pick-up Service Available!

apartment, Fujikawaguchiko Town

Mt.View B棟, a three-bedroom house in a quiet Fujikawaguchiko residential area, is located 0.85km from the Stella Theatre and within easy walking distance of a supermarket and Seven Eleven convenience store.
This recently renovated property sleeps six guests, offering a kitchen with fridge, freezer, and microwave, air conditioning, parking for two cars, and excellent internet access; Mount Fuji views may be possible on clear days.

9.5 206 reviews

Minamitsuru-gun - House - Vacation Stay 82667

house, Fujikawaguchiko Town

This charming house is located in Fujikawaguchiko Town, just 2 kilometres from Lake Kawaguchi and 5 kilometres from Fuji-Q Highland, offering easy access to the area's popular attractions. The house has consistently received excellent ratings for its cleanliness, location, and overall experience.
The house spans 133 square metres and features four bedrooms, a living room, a fully equipped kitchen, and a bathroom with a bidet and bath. Guests can enjoy a private patio with mountain views, free Wi-Fi, free parking, and free bikes, as well as access to nearby hot springs and a garden.

9.3 143 reviews

Habitacion Cottage Suzu

apartment, Fujikawaguchiko Town

Habitacion Cottage Suzu is a recently renovated apartment in Fujikawaguchiko, conveniently located 3.1km from Lake Kawaguchi, 4.3km from Fuji-Q Highland, and 2.3km from the Lake Kawaguchi Ohashi Bridge.
This 70 square metre self-catering property sleeps seven guests and features two bedrooms, one bathroom, a fully equipped kitchen, free Wi-Fi, parking, and is situated in a geothermal area with access to nearby hot springs.

9.8 83 reviews

湖畔まで徒歩2分｜貸切宿で四季のイベントを満喫。バス停、コンビニまで徒歩1分。

apartment, Fujikawaguchiko Town

This three-bedroom apartment, sleeping up to ten guests, is situated in Fujikawaguchiko town, a mere 0.16km from Lake Kawaguchi and within 0.16km of both a 7-Eleven and a FamilyMart convenience store.
The property boasts a fully equipped kitchen with fridge and microwave, air conditioning, and is conveniently located near the Music Forest Museum bus stop, offering easy access to local attractions; exclusive private rental ensures complete privacy for one group per day.

Places to stay in Lake Kawaguchi