Windmill Hut
The Windmill Hut, and known as "?", most famously located in OoT's Kakariko Village, is home to Guru Guru. It is connected to Dampe's crypt, and draws its power from the Well. Link can teach and learn the Song of Storms to/from Guru Guru here. The story is a very odd one. Basically, Adult Link is taught the song by Guru Guru (who claims to have learned it from a horrid little Ocarina kid). Then by travelling back seven years, Link then goes and teaches the tune to Guru Guru in the first place. Where exactly did it come from? No one really knows.
The Windmill is also in Oracle of Seasons, though more as a cameo. Guru-Guru plays a role in the trading game for the Noble Sword.