In the middle of the Hierapolis ruins lies a swimming pool unlike any other in Turkey. An earthquake in the seventh century tipped a row of marble columns from a portico of the Temple of Apollo into the warm spring that fed the ancient baths. The columns settled where they fell, and the pool has been used for bathing ever since. Locals call it Cleopatra's Pool on the unconvincing legend that Mark Antony gave Hierapolis to the Egyptian queen as a wedding present.
The water is around 35°C, gently fizzy with dissolved minerals, and clear enough to see the corinthian capitals and column drums lying on the bottom. There is an extra entry fee on top of the Hierapolis ticket, plus a charge for lockers and a towel. Avoid the middle of the day, when tour groups arrive in waves; mornings and late afternoons are calmer.