People with a head for heights are taking part in the first Great Yorkshire Stair Climb (GYSC).
They are heading to Yorkshire's tallest building, Bridgewater Place, to tackle the 522 steps to the top of the 112 metre high building. All the proceeds raised will go to the Yorkshire Cancer Centre.
Everybody taking part will be time, but it's up to the individual whether they steadily walk up or sprint two steps at a time.
One of the people taking part is Dan McIntyre, a wheelchair user who finds it challenging to walk short distances, has had kidney failure and is a two time cancer survivor.
Unfortunately, Dan has been out of work for the past few years, but has filled his time volunteering for various charities (most notably Bradford Cancer Support and Airedale), and taking part in various challenges to raise much needed funds.
Last year he did the Alps Challenge for Disabled Motoring UK, where he took a 1932 mobility trike the 1800 mile distance across the Swiss Alps, recreating the epic journey undertook by the trikes former owner back in 1947. He participated in the Leeds 5k as part of the Jane Tomlinson Run for All in aid of the Yorkshire Cancer Centre, taking him 80 minutes to complete. This year Dan zip wired from the Tyne Bridge in Newcastle, on the very same line that Bear Grylls used the previous day with the Olympic Torch.
The event is open to people of all abilities over the age of 16, and costs £20 to register. Further information about the event is available here website.**