El Rastro is Madrid's great flea market, comparable in some ways to Portobello Road in London and the Marché aux Puces in Paris, but with a unique Spanish flavour. The human panorama here is at least as interesting as the things offered for sale. It is an experience not to be missed by a tourist visiting Spain: a teeming mass of bargaining, socializing and buying people, ranging from the poorest (some salesmen look like they sleep under a bridge) to the smartest (look out for those pickpockets).

On ordinary weekdays, it is a collection of open-air shops that sell new and second-hand articles of all kinds. On Sundays and holiday mornings (and to a lesser extent Saturdays as well), El Rastro reaches its zenith. It becomes a true flea market, with booths and stalls filling the streets within the triangle formed by the San Isidro Cathedral, the Embajadores and the Puerta de Toledo roundabouts. Calle (street) Ribera de Curtidores and its adjacent streets and alleys are the central axis. For more than half a millennium this area has been a living and literary legend, but tales of finding Goya paintings and Roman coins are now a thing of the past. Today, the stalls offer second-hand goods, antiques, new goods at below market prices (often fake Nike's or touristy hats and sunglasses), crafts, etcetera - altogether an amazing assortment of wares.

Traditionally you were expected to bargain, but not anymore when I paid El Rastro a visit a few years ago. The incredibly crowded market is a haven of petty thieves, so hang on to your belongings. El Rastro is also known for its fake antiques, so don't pay over the odds. Just let yourself be carried along by the flow and enjoy this glimpse of real Spanish street life.