There are two underwater sightseeing boats, and when you enter both of them, you will see the cobalt blue of the lake through the window.
The window is located 2m deep and measures approximately 70cm square.
Approximately 16 windows make the lake bottom look all the way.
Of the two ships, the Emerald is two stories behind the deck, and the Sapphire is the submarine type that can stand at the front of the ship.
Both passenger capacity can accommodate up to 50 people.

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Column joints

Below the surface of the lake is a steep, cliff-like view known as "column joints."
This is a crack that was created when the magma suddenly cooled and contracted during the formation of the caldera, and is the highlight of Lake Shikotsu.
The clear view of the lake bottom will make you feel as you recognize the high transparency of Lake Shikotsu.
The wild rocks and ripples of sandy ground that look like they were written in a brush...The natural beauty of sculpture that is usually hard to see is a world unique to Lake Caldera.
If you're lucky, you can also find chips (Himemasu).
Not only is the beauty of the lake, but the nature surrounding the lake is also a major highlight.
The contrast between blue and greenery created by nature creates a wonderful landscape.