Pyramid Hill Sculpture Park, located in Hamilton, Ohio, is a unique place to visit. I took my kids here a couple of years ago, and they had a great time exploring the huge sculptures. The underground pyramid-shaped house, which is now a museum, is set in 265 acres of park-like grounds featuring 37 contemporary sculputures, gardens, 7 lakes, and quite a few hiking trails. The museum contains displays of Roman, Egyptian, and Greek sculptures that are thousands of years old. In fact, the goal of the museum is to have a collection which will demonstrate the complete history of sculpture by mankind.
The grounds are open year-round from 8:00 AM to 5:00 PM. The museum is oepn daily, from 12:00 PM - 5:00 PM. Admission is $8.00 for adults, and $2.00 for children.