One for the supreme history fiends on a hunt for the remnants of Halicarnassus, this gate is the last remaining chunk of King Mausolus' once sturdy fortress walls, which wrapped around the ancient city for seven kilometers. 

For tourists who enjoy a bit of poking about, plenty of small ruins are nearby, including a scattering of tombs and mosaic fragments left in situ, as well as the sparse remnants of a 4th-century BC moat. 

None of these remains in themselves have a wow-factor, but combined they make an interesting hour or so of exploring.