Gaping Gill in Yorkshire opens just twice a year, giving a glimpse into one of the longest and most complex cave systems in the UK. Gaping Gill in Yorkshire is open just twice a year. Nowadays, the main chamber is floodlit but visitors can use a torch to explore the nooks and crannies of the cave. The main cave is 420ft long, 100ft high and 82ft wide. A potholer is winched into Gaping Gill over the main shaft entrance.

Source: Daily Mail May 19, 2019 15:11 UTC