In his cave.
His human hair cave.
No, that's not a metaphor.
The "collecting" began in 1979, when Galip thought he might boost participation in the pottery courses he taught in his shop above the cave ... by collecting hair samples from participants and hanging them on the cave wall beneath the studio. We can only take his word that this was actually how he procured all those samples and that there aren't 16,000 shriveled heads silently screaming for release from their cavernous coffins.
Colored note cards would have looked a lot less like dessicated scalp.
Undaunted by the lack of escape routes, women apparently continue to shed a lock for Galip's collection to this day. And if a visitor sees a tress that tickles his creep fancy, he might be able to find the owner. For you see, Galip thoughtfully COLLECTED ADDRESSES WITH EACH LOCK OF HAIR.