A tiny 27-square-metre cocktail bar designed by the architect Adolf Loos in 1908, around the corner from the Graben. The polished mahogany ceiling, the onyx panels on the walls, the brass fittings, the mirrors arranged to make the room appear vastly larger than it is — all original.
The bar is now a listed monument and one of the most famous pieces of early-modernist interior architecture in Europe. The cocktails are well made and not too expensive given the setting (around 14 euros). Doors close at 4am most nights. Get there early or expect to wait.