Mount Zao (蔵王山) is a group of volcanoes between Miyagi Prefecture and Yamagata Prefecture.
The highest peak is 1,841 meters high and is the hightest mountain in Miyagi Prefecture.
The peak is located about 40 km west-southwest of Sendai city.
And, the nearest city in Miyagi Prefecture is Shiroishi city.
The peak of Mount Zao is about 23 km northwest of Shiroishi city.
It is a crater lake and is located only 1 km southeast of the highest peak.
The lake is nearly round, and the diameter is about 330 meters.
The depth is about 27 meters.
And the water has a strong acidity.
The beautiful green color of water changes every hour by movement of sun.
So it is also called Goshikinuma (五色沼, Lake in five colors)
This lake is the most popular spot in Mount Zao.
A few scenic overlooks are near the mountain pass or the peaks by Zao Echo Line which is a highway passing the mountain of Zao.
But the highway is closed from early November to late April, so we can't visit the lake in the period.
There are Zao hot spring and ski resort on the west side of Mount Zao.
They are in Yamagata Prefecture, so see this page about them.
How to get here
While the highway is opened, express bus to the view point is operated only on Saturday and Sunday.
It starts from Shiroishi-Zao station of Shinkansen, stops at JR Shiroishi station, and go to "Zao Katta Sancho" observatory.
The start times at Shiroishi-Zao station are around 9:30 and 10:30.
It takes about 1.5 hours.
After about 50 minutes, the bus returns to Shiroishi city.
In addition, the route bus for Zao Onsen and Yamagata station starts at around 14:00 from "Zao Katta Sancho" stop.