Panty Tree

Under some ski lifts, there are trees decorated with bras and panties – people riding the lifts seem to throw it there, and then it keeps growing by interesting social dynamics.

According to the Skiing Heritage journal, the practice might have begun in the 1950s.

See also: Schuhbaum (by the way, there's is now a shoe tree very close to where I live, and I'm really happy about that! :D)