In Prague, you probably need to consider both, as demonstrated by the map of door handles1 that complements the skyline of towers and castle. You can imagine many similar maps, depicting turrets, manhole covers, front doors, hand water pumps or balustrades.
The map is linked to a Facebook page named “Pražské vycházky – architektura, historie, příroda” (Prague strolls – architecture, history, nature) where the author invites readers to send more photos but also seems to be unsure about the further procedure.
Source of image here.
- In continental Europe we rarely use round knobs, apart from some hotels that obviously seek to accommodate guests from “knobish countries”. I assume that in old times you often had to apply your full body weight in order to move the mechanism. ↩