Lake Mashu
A beautiful and mysterious lake
Known as “Kamuito” (lake of the gods) in the Ainu language, this caldera lake has a circumference of approximately 20 km and a maximum depth of 212 m. It boasts the world's highest level of transparency. The deep blue color of the lake is called “Mashu blue” due to the reflection of the sky color on the transparent surface of the lake, and the blue color is even more polished on days when there is no wind.
The lake is surrounded by a 150m to 350m caldera wall and has no rivers flowing into it. Although it is not possible to approach the surface of the lake, visitors can view the lake, Kamuishu Island floating there, and Kamuinupuri (Mt. Mashu) rising up beside the lake from the three observatories, Mashu Observatory No. 1, Mashu Observatory No. 3, and Uramashu Observatory.
Lake Mashu became famous for the song “Foggy Lake Mashu,” and as the name of the song suggests, the lake is covered in fog about 100 days a year, and is often seen from June to July. Both the shining blue Lake Mashu and the misty Lake Mashu are so mysterious that you cannot help but admire them.
- * Please note that the text shown on this page includes machine translations.
- Category
- With friends
- Solo trip
- Guys' trip
- Girls' trip
- Couple
- Travel style
- Activities & Outdoors
- Winter scenery, drift ice
- Lake and marsh, waterfall, pond, dam
- Red leaves, scenic spots, observation platforms
- Natural scenery, spectacular views
- Skiing, snow activities
- Visit seas, rivers, and lakes
- Travel Inspiration
- Enjoy spectacular views
- Picturesque spots
- Nearest airports
General Information
- Postal code
- 〒088-3222
- Address
- 北海道川上郡弟子屈町原野
- Telephone Number
- 015-482-1530（Lake Mashu Rest House）
- Car Park
- Parking fees apply
- Directions
- ●By Bus: About 25 minutes from JR Mashu Station to Lake Mashu Observation Deck 1
●By car: About 120 minutes from Doto Expwy Ashoro IC
※The third Observation Deck is approximately 40 minutes on foot from First Observation Deck. There is no public bus to reach there, so please use a tour shuttle bus or private transportation. - Website
* Information on facilities is subject to change. Please check each official website for the latest information.
