 A paved trail less than 1 / 4 mile (400 m) long at North Crater Flow (photo) crosses the North Crater Lava Flow, which formed about 2200 years ago, making it one of the youngest lava flows on the Craters of the Moon Lava Field. This lava is named for the purplish-blue tint that tiny pieces of obsidian (volcanic glass) on its surface exhibit. Good examples of pahoehoe (ropey), aa (jagged), and some block lava are readily visible along with large rafted crater wall fragments. The rafted crater wall fragments seen on the flow were once part of this cinder cone but were torn away when the volcano's lava-filled crater was breached. A 1.8-mile-long trail (2.9 km) includes the 1 / 2 mile (800 m) overlook trail but continues on through the crater and to the Big Craters / Spatter Cones parking lot.
