Well, shiver me TIMBERS!! Er, Zimmers, that is...
One must assume that rooms were usually made out of wood.
When I was traveling both in Germany and Austria, I always asked (in poor German) if there was a “Zimmer” in the vicinity. Before the advent of the Euro, one could get amazing deals for a Zimmer, now they’re more expensive.
Actually shiver me ZIMBERS! Try that 10 times! ;-)