Florence, centre of the artistic world, cradle or Italian medieval history.
On our first visit we hated it.
My wife and my memories of Florence on our first visit are a mix of heat, dust, bad smells and getting lost (a lot). Roses were covered in a fine dust, the sun became a burning pink ball each evening, we witnessed the collapse and imminent death of a tourist, a messy moped accident resulting in a broken arm that still managed to be waved about in conversation, warm pools of urine (human or horse, not sure) and the most frustrating map I have ever used (all of the marked streets were the same size, from two lane roads to cramped alleyways).
It did not help that on the night of our arrival we wandered into the market area around dusk, entering a seedy world of hawkers, beggars, dodgy looking types and market stall holders at the end of a long day. This was the only time in our trip we felt genuinely skittish.
Contrast this with our arrival in Seina in the middle of a medieval festival, complete with parades and a race through the Piazzo Del Compo to see who will ride in the Palio. It was a furious and thrilling first two hours until the clouds burst clearing the piazzo in seconds!
Porcellino, the enormous brass bore in the market area has a shiny nose from being rubbed by tourists. Apparently if you rub it you will return. "Touch that and you are coming back on your own" my wife said and she meant it.
Oddly, many of my favourite images from that trip came from Florence and it was one of the better hotels we stayed in, although not great. The worst hotel was in Siena, but we have much better memories of that city, go figure.
The second trip in winter a few years later could not have been more different. Our hotel was an off season revelation, the people were softer, even in the market area (the global down turn humbled many) and soft rain cleaned the streets, as did the police, seemingly less tolerant of corner hawkers.
We did not rub Porcellinos' nose, but we came back anyway. An open mind really can open new (or old) doors.