Cragged rock formation and cloudy sky from Craters of the Moon National Monument & Preserve near Arco, Idaho (USA). HDR composite from multiple exposures.
Self-titled Lunatic Rock for what looks like an abstract face of a crazed monster. Title also inspired by etymology in that "lunatic" derives from the Latin word "luna" meaning the "moon", in turn echoing the name of the park where this rock is located (Craters of the Moon).