1) HârnWorld, for not-quite medieval goodness, magnificent maps, and staggering detail.
2) Glorantha, for outright strangeness, my runes are death, truth, and death.
3) Arthurian Britain, for the glory and tragedy of knighthood.
4) 1920’s New England, because I’ve lost my sanity.
5) The world of Earthdawn, because of an elven archer and a gay wizard.