This month the doors to many places you don't normally get to see are being unlocked. It's part of an initiative to celebrate the architecture and heritage of Wales, which gives the public access to a variety of buildings and heritage sites across the country.
Rob Shelley visited Llanberis' old quarry hospital to find out more.
A man climbing the Llanberis Pass in Snowdonia was trapped for three and a half hour after his arm was jammed in a crevice on Sunday. The 28-year-old man from Aberdyfi in Gwynedd was on a climb known as Noah’s Warning, 1,000ft up Dinas Cromlech.
He was in a party of four when he slipped and his arm became wedged in rocks. He was eventually freed by the Llanberis mountain rescue team, firefighters and a group from of cave rescuers from Flintshire. He was flown to hospital in Bangor by RAF Sea King helicopter.