Twelve miles from downtown Juneau is the Mendenhall Glacier, the most famous glacier in the Juneau Ice Field. Besides the visitor center, the glacier is surrounded by hiking trails suitable for a variety of fitness levels that don't require training or gear. More adventurous options are to take a helicopter ride over the glacier or sign up for a trek across the ice. You'll be outfitted with the appropriate climbing gear and then flown by helicopter onto the surface of the glacier where a guide will lead you across the fascinating glass-like surface. Water can be seen running directly beneath your feet, allowing you to claim you can walk on water. Weather and pressure changes have caused the glacier to buckle in places, creating a shingle-like world of crystallized ice walls great for basic climbing and rappelling. Crevices reveal pools of the bluest, and perhaps tastiest, water you may ever encounter.