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Piazza del Campo (Siena)

Italy / Toscana / Siena / Piazza del campo
 square, horse racing track

Famous for the annual Palio - a horse race of three laps of the square.

Each district of Siena has it's own team and organises it's own horse and jockey in this race which takes over the entire town for weeks on end leading up to the big day. Rumour has it that the result isn't so much the ability of the rider and horse but more to do with backroom dealings and money changing hands.

The Wiki link explains a lot but there's far more in real life - parades, colourful flags. In fact the event was used as the backdrop to one of the Martini adverts broadcast on UK TV in the late 70's.

If you get a chance to see a race (unlikely) or to watch a TV program about the event then do so - most interesting.
en.wikipedia.org/wiki/Palio_di_Siena

Edit: another good link to the Palio can be found here
www.initaly.com/info/palio/palio.htm
Nearby cities:
Coordinates:   43°19'6"N   11°19'54"E