Cinder Cone and the Fantastic Lava Beds lava and has concentric craters at its summit, which have diameters of and . Cinder Cone is comprised by five basaltic andesite and andesite lava flows, and it also has two cinder cone volcanoes, with two scoria cones, the first of which was mostly destroyed by lava flows from its base. Cinder cone volcanoes are typically monogenetic, meaning that they only undergo one eruptive period before ceasing activity forever. These eruptions often consist of the ejection of tephra, though they may also generate lava flows, which often originate from vents near the base rather than the summit of the volcanic
West Rock Ridge is a dark colored rock, but the iron within it weathers to a rusty brown when exposed to the air, lending the ledges of West Rock Ridge a distinct reddish hue. The rock, which formed 200 million years ago during the late Triassic and early Jurassic periods, frequently breaks into octagonal and pentagonal columns, creating a unique "postpile" appearance. Huge slopes made of fractured rock scree are visible beneath many of the ledges of West Rock Ridge. The ridge is the product of a huge feeder dike that supplied several massive lava flows hundreds of feet deep that welled up