The most recent glaciation began about 35 000 years ago when climate turned much colder and wetter and glaciers began to grow in the nearby mountains. Glaciers flowing from Vancouver Island and the Coast Mountains filled the Strait of Georgia with 2 km of ice and buried nearly all of Vancouver Island. Craggy Mount Arrowsmith protruded above the ice as a 'nunatak', whereas lower peaks, such as Mount Benson near Nanaimo, were completely overrun, rounding their summits.