The weirdest alleyway of Prague is located not far from the Vltava river and Charles Bridge, on the Castle side. It connects the street U Lužického Semináře with a little courtyard on a lower level. With only 50 cm (about 20 inches) width at its narrowest point, two people would find it really hard to pass each other in the middle of the stairs.
So the Czechs came up with a very pragmatic and unusual solution: They installed traffic lights at the top and the bottom ends.
So enjoy the walk, don’t get stuck, and don’t forget to press the button, or you’ll wait forever!