In fall, their leaves turn red or yellow. This region offers a good habitat for animals like deer and monkeys. Char are swimming in the stream and a gray wagtail is hopping from rock to rock. The Chichibu District has a number of mountains made largely of limestone. So, there are a lot of limestone caves.
Ground water erodes the limestone little by little, forming caves of varous size.
Temperatures in the cave remain virtually constant through the year. Cave animals, like bats, live here in the darkness. These forests are under the protection of the Japanese Government. The ground in these forest is covered with moss. A large topographical model of Saitama occupies the center of this hall, and in the model localities of rocks, fossils and other geological phenomena are shown by small red lamps.