Look up at the cone tips of trulli as you walk through Alberobello and you will notice two things: the removable stone pinnacle at the very top, and — on many cones — a symbol painted in white limewash on the grey stone. Crosses, circles, crescents, stylised figures, arcane geometric forms. No two buildings share quite the same mark.
The symbols are one of the genuine mysteries of the trulli. Some appear to be Christian: the IHS monogram, anchors as symbols of hope, crowns for the Virgin. Others look older and stranger — pre-Christian markings possibly connected to beliefs absorbed from the Greek and local Italic populations who inhabited this area before the Norman conquests. The honest answer is that no one fully knows: many symbols were simply the marks of individual builders or families, a kind of signature, while others carried protective or devotional meaning. Standing in the lanes of Rione Monti, reading the roof-tips like a code you almost but cannot quite decipher, is one of the more quietly fascinating things you can do in the town.