Petroglyph Tuff Ring 4. Aerial view looking southeast over the eroded tuff ring that hosts the Petroglyphs section of Lava Beds National Monument. The tuff ring formed when eruptions occurred in ancient Tule Lake about 275,000 years ago. The steep right-hand (western) face was used by Native Americans to carve petroglyphs into the soft rock. Photograph 5 was taken at the base of the cliff. Photograph by Julie M. Donnelly-Nolan.