An ice cave, which forms naturally on a high-altitude glacier in the Swiss Alps brought delight to nature lovers and photographers. The bluish cave, which varies in shape each year, has a rounded ceiling made of thick ice about 5 metres high, and is about 20 metres long. The tunnel is accessible by foot in 15 minutes from the chairlift at Glacier 3000 above the resort of Les Diablerets, but at your own risk, organisers said.