This is probably the largest park in the Nasushiobara area.
Like most parks in Japan it is worth visiting in the different seasons because its character changes a lot with the seasons. There is a fountain with a shop, little hall (we once saw a bonsai exhibition there) and a place you can rent bicycles. There is a beautiful wooded area. And a very nice field which is great for a picnic. There is a nice view from the hill area. I bet it would be a good place to go for a run, though its some distance from downtown so you couldn't run to it (and I hate driving to go for a run).
This is a great park for kids. There is a large playground area. And a great obstacle course. You have to pay a small amount to use the course. Both of them are sensational. These are not your watered down, wimpy, low litigation playgrounds found in Australia or USA. These are exciting and slightly dangerous playgrounds of my youth. I had a lot of fun on the obstacle course.
There is also a rather prominent, kitch windmill which I hate.
See also Nasushiobara Cherry Blossom