The Manis Mastodon site is a 2-acre (1 ha) archaeological site on the Olympic Peninsula near Sequim, Washington, United States, discovered in 1977. During the 1977-78 excavation, the remains of an American mastodon were recovered with a 13,800-year-old projectile point made of the bone from a different mastodon embedded in its rib. The site was placed on the National Register of Historic Places in 1978.