In far eastern Russia, north of the Kamchatka Peninsula, lies Anyuyskiy Volcano.

Now dormant, the volcano was once active enough to send a massive lahar—an avalanche of volcanic ash and rock mixed with water—50 kilometers (30 miles) down the west side of the volcano summit. The dried, hardened remains of the lahar persist today, a streak of barren rock on a landscape that is otherwise richly vegetated.


Read more: earthobservatory