21st Century Forest and Square is a nature-respecting city park located in Matsudo City, Chiba Prefecture, Japan.

The park opened on April 29, 1993.
The area is the size of 11 Tokyo Domes. Sendabori Pond alone is about the size of one Tokyo Dome.

In addition to the vast lawn plaza, there is the Matsudo Municipal Museum, Mori Hall 21 (Matsudo City Cultural Center), and a barbecue plaza, which is crowded with vacationers with parents and children and people who have picnics on holidays.

This time, on weekday mornings, a ship was flown from "Light and Wind Square" to "Sendabori Pond".