Designated a National Natural Landmark in 1973, Amboy Crater was recognized for its visual and geological significance. Although Amboy Crater is not unique, it is an excellent example of a very symmetrical volcanic cinder cone.
The inside of the 250' high crater contains two lava dams behind which has formed small lava lakes. These are now flat in general appearance, covered with light colored clay, creating the impression of miniature "dry lakes." There is a breach on the west side of the crater where basaltic lava poured out over a vast area. Beyond the crater lies 24 square miles of lava flow containing such features as lava lakes, collapsed lava tubes and sinks, spatter cones and massive flows of basalt.
