For three centuries, on the order of Pope Innocent XIII in 1723, the stairs were encased in protective planks of walnut wood, preventing the many worshippers who climbed on their knees from touching and damaging the marble surface. Their wood covering is now being restored, however, so until June 9, the faithful have the rare opportunity to touch the original steps.
Photo: Mateusz_Szymanski/Shutterstock
The restoration is the first time the 28 steps have been exposed since a cleaning in the 1950s, and many objects have already been found under the wood, including coins, photos, handwritten prayers, and rosaries. The frescoes around the staircase were recently restored.
If you’d like to take advantage of the rare opportunity to ascend the bare stairs, you must do so before June 9, the Feast of Pentecost, when the casing will be re-installed. The inauguration, which will take place from 3:30 PM to 5:30 PM on that day, will include a presentation of the restoration, a benediction of the Stairs, and a holy mass. 
H/T: Smithsonian.com