There are more restaurants in Madrid that you would think possible, with Tapas bars on almost every corner, as well as more elegant fine dining establishments. Reservations are not always necessary, although if you choose a busy restaurant on a busy night, it pays to book in advance, rather than be embarrassed at the door.
The oldest restaurant in the world according to the hype is Botin, which first opened in 1725, and serves a variety of traditional Castilian food from its basement location on Plaza Mayor.
Jockey is a popular fine dining restaurant specialising in seafood, although their menu is extensive. Open since 1945, it remains fashionable and is often very busy; you can find Jockey on Amador de los Rios.