Bramante staircases, Helical stairs in Vatican Museums, Vatican City.

The Bramante staircases are two helical stairs in the Vatican Museums. The original, in the Pio-Clementine Museum, is a gently sloping ramp of herringbone paving carried on 36 granite columns that thin toward the top, with the five classical orders changing at each full turn. The 1932 stair by Giuseppe Momo is a double helix of pale stone with dark treads, its ramps edged by wide bronze-colored balustrades in relief.

Bramante designed the first ramp in 1505 for Pope Julius II to create a direct path between the palace and gardens. Giuseppe Momo later took up this solution and built a new spiral staircase in metal and stone.

The name honours Donato Bramante, whose 1505 ramp was long mistaken for the exit spiral visitors descend today. That modern stair, designed by Giuseppe Momo in 1932, has a balustrade sculpted by Antonio Maraini and cast by the Ferdinando Marinelli Artistic Foundry. Its two helices let people pass without meeting, and some professors link its skylit atrium to Frank Lloyd Wright's Guggenheim.

The modern staircase by Giuseppe Momo, from 1932, is the route all visitors take at the end of the museum tour. Its two separate helical ramps let people descend without meeting those coming up. The stairwell is about fifteen metres wide, with a canopy above that lights the steps.

The Renaissance ramp was built so that riding animals and carriages could roll along it, which is why its slope remains gentle. Granite columns line the way and support a vault that runs continuously from top to bottom.