Yunohama is very close to Tsuruoka and can easily be accessed by bicycle via a special path near Zenpoji. The main attraction of Yunohama are beaches on the Sea of Japan, followed by Yunohama's onsens.
Here are some beach hotels at Yunohama.
Here is Peter on the beach when it was too cold to swim. We biked to Yunohama after visiting Zenpoji. It was sunny out, however, and Peter capitalized on this by doing his FBI agent impression.
The mountain in the background is Chokai, which is on the border of Shonai and Akita. The top of Chokai is cut off due to the clouds but it has a rather nice shape.