The picture shows a sign that says "Welcome to Turkey" in English and Turkish. The sign is placed at the border of Turkey, indicating that visitors are entering the country. The joke is that the sign is placed in a way that it seems like the sign is welcoming people to Turkey even though they are already inside the country. This is a common joke in Turkey, where people often make fun of the government's bureaucracy and sometimes lack of logic. In Turkish, the joke can be explained with the phrase "İçerdeyiz zaten, neye hoş geldiniz?" which translates to "We're already inside, why are you welcoming us?"