The Ephesus I visited is in Turkey...most people would be satisfied with 2 - 3 hours. It is a fascinating, eye-opening place not only for the relics of buildings but because Biblical figures were there. Mary is said to have had a small house nearby, and a couple of boys were secretly try to sell us fake relics of John the Baptist. When I was there about nine years ago, it was remarkable little had been done to cater to or control tourists...cows wandered at the entrance with no fencing, it wasn't crowded, and the whole experience was lovely.