ROME, ITALY - JUNE 03: Illustration of Rome; Italy on June 03, 2012. .The treasures of the Vatican. Exit: stairs double helix..The Vatican Museums spiral staircase is one of the most photographed in the world, and certainly one of the most beautiful. Named by mistake "The Bramante stairs", but designed by Giuseppe Momo in 1932, the broad steps are somewhere between a ramp and a staircase. The stairs are actually two separate helixes, one leading up and the other leading down, that twist together in a double helix formation.