Diporto is one of the most famous restaurants in Athens — though "restaurant" sells it short. It is a 130-year-old cellar taverna in the basement of a building on Theatrou Square, near the central market. There is no sign, no menu, no telephone reservation, no website. You walk down the steps and the owner brings you whatever is being cooked that day. Usually chickpeas, often grilled fish, always cheap.
The wine comes from barrels along the back wall, served in tin jugs. The clientele is half tourists who have read about it and half market workers on their lunch break. Open lunchtimes only. Closed Sundays. Cash only. Bring a friend; the food is shared.