In many of Lviv’s old buildings there is a porte-cochère, a passageway through a building designed to let carriages pass from the street to an interior courtyard. Along the sides of the porte-cochère is an elevated platform, which functioned as a sort of sidewalk for people to be able to walk past a carriage or other vehicle in the driveway. It also served as a curb for the carriage to prevent it from bumping into the walls, holding a similar purpose as the guard stones, which often flank the doorways. Maybe it could have also been used as a carriage step.
Most are stone, but I have come across a few wooden ones.