The George C. Page Museum, part of the Natural History Museum of Los Angeles County, was built next to the tar pits in Hancock Park on Wilshire Boulevard. Construction began in 1975 and the museum opened to the public in 1977. It tells the story of the tar pits and presents specimens from them. Visitors can walk around the park and see the tar pits. On the grounds of the park are life-size models of prehistoric animals in or near the tar pits. Of more than a hundred pits, only Pit 91 is still regularly excavated by researchers, and can be seen at the Pit 91 viewing station, which is outside the museum, and free to enter. Currently, Pit 91 excavations have been put on hiatus so that excavators can operate year-round on material from Project 23. Paleontologists supervise and direct the work of volunteers.