Complex sentence: Mammoth Mountain is home to the Mammoth Mountain Ski Area which is notable in that it gets an unusually large amount of snow compared to other Sierra peaks, due to Mammoth Mountain lying in a low gap in the Sierra crest.
Split into simpler sentences: Mammoth Mountain is home to the Mammoth Mountain Ski Area. The ski area gets an unusually large amount of snow, due to Mammoth Mountain lying in a low gap in the Sierra crest.