There are few things legally available that are guaranteed to give as much pleasure as a glass of something and a bite to eat. Add to these the company of friends and time spent taking in sights and smells, and you have a day well made. A day spent, ladies and gentlemen, on tapas safari.

Tapas are a Spanish creation, born of necessity and invention, either (depending on whom you listen to) when enterprising bar owners put a slice of bread over glasses of sherry to deter the flies (tapa means lid or cover in Spanish), or by King Alfonso X, who, sometime in the 13th century, and largely due to illness, was unable to drink wine between meals unless it came with small mouthfuls of food. Once recovered, he liked the idea so much, he decreed no tavern should serve wine without a morsel to go with it.

Whatever its roots, there’s no better place to go hunting this cultural institution than Barcelona, where it thrives in all its sizes, shapes and various plumage. So, after careful preparation (no breakfast), I rounded up my brave posse of fatsos and began the day in Barceloneta, the area of beaches around the old port at the bottom of Las Ramblas.

In the middle is the covered market, a newfangled thing that, from the outside, can’t decide if it’s a ship or a nightclub. Overlooking this metal monster and rolling its eyes is Can Ramonet (Placa de la Maquinista 17; 00 34-93 319 3064, www.elnouramonet.com), one of the oldest premises in the area, dating from 1763.

We sat outside and began with a jug of cava sangria (£9) – cava with soda water and slices of lemon and orange – as a palate-cleanser. Then, with muttered “good lucks” and a brief prayer, our ordeal began: perfectly grilled razor clams, fried baby squid in a beautifully light batter, ham croquettes that were thick and sticky, and chipirones fritos, the edible version of Russian roulette. The small, green peppers are fried until their skins blister, then coated in sea salt.

There’s always one that packs unprovoked heat, stinging the gums and making you gurn.

Next on our tour was Sagardi (Carrer de l’Argenteria 62; 93 319 99 93), in the shadows of the gothic church of Santa Maria del Mar, in El Born. You could easily spend the day in this district, with its Picasso museum, plentiful boutiques and too many bars. But find time for Sagardi – a first-rate place to nibble and natter.

The long counter is topped with up to 20 plates of hot and cold morsels on top of slices of crusty bread, each speared by a cocktail stick. When you’re done, the waiter counts the number of sticks lying on your plate, like bloody daggers on an evidence table, and charges £1.20 for each. And here’s a thing: you never see any thrown on the floor.

The food is typical of the Basque region, and is well set off by an inch or two of home-brewed cider, poured from a height from barrels behind the bar to oxygenate the cloudy, noncarbonated liquid. Highlights included crab mayonnaise on sweet croissant; cream cheese and blueberry jam; tuna and stewed cabbage; bacon, cheese and prawn tortilla; and, the best, an oily chorizo sausage, terracotta red with pimiento colouring. After that, we paused.

BUT NOT for long. From the traditional to the modern: Paco Meralgo (Carrer de Muntaner 171; 93 430 9027, www.pacomeralgo.com) is a welcome 30-minute walk towards the centre. The linguists among you will be smiling – the name is a play on the Spanish for “to eat something”, para comer algo.

So we did. Bomba, a spicy potato fritter with parsley, ham and chilli, covered in a cream sauce, and Galician crab, served in a ramekin shell with herbs, were both exquisite. It was like eating in high definition.

Three down. Next, an old favourite, Cerveceria Catalana (Carrer de Mallorca 236; 93 216 0368), which is always packed. The front is split in two: hot food prepared on the left, cold on the right, with orders shouted angrily between them. Fight for space at the bar or give your name to Bady, the hostess, who will seat you, eventually, in the back, where bottles of beer line the walls like books in a library. We were slowing down, but still managed to squeeze home some crimson ham, the stripe of opaque fat circling the vivid pink meat like the collar of a City shirt, and a portion of patatas bravas, which were crunchy and bold, and went down way too easily with a bottle of beer.

We had one more stop on our list, but we’d hit a snag. We couldn’t move. After a vote, we decided to save Santa Maria until the following day. And thank the saints of every persuasion that we did.

Santa Maria (Carrer del Comerc 17; 93 315 1227) is run by former students of Ferran Adria, the master chef at the gastronomic playground of El Bulli. So, while this is still tapas by name, you’ll find nothing that you’ve already eaten replicated here. Our waitress explained that groups of five or more are obliged to have the tasting menu, at £22 per person. So we settled down, ordered some wine and began. Again.

Ready? First was homemade lemonade with mint leaves, which was summery and refreshing. I was still full from the day before, but I ploughed on – for you, let it be noted, only for you – as a bowl of sardines with pineapple, strawberries, avocado and seaweed arrived. It sounds horrible, but it wasn’t. Very little was. Slices of octopus were cutely done; a fist of white fish on a white-bean purée was delicious. Dishes came and went. I’m sure there was a bowl of curried crisps in there somewhere. A few weren’t so successful – a mussel salad was a mess of lettuce, and a crab-and-potato combination failed to taste of anything. But we’d done well. Then I realised something that sent a shiver down my fork. They were just the starters.

Better, much better, was to come. Duck liver and fig was very naughty, but by God it was good. Octopus roe was big and meaty. There were others of every hue and flavour, but I missed the waitress’s description because I had my fingers in my ears to stop the starters escaping. And then ... dessert. Yoghurt-coated cornflakes with raisins; the poshest, the very poshest tiramisu; “Dracula” mousse, full of blackberries, with popping candy straight from the 1980s at the base. To finish, little chocolates so rich, each one was a millionaire.

Everyone agreed it was extraordinary. Everyone except the vegetarian, who had been unable to join in on almost anything. If you don’t eat fish or meat, in Santa Maria you don’t eat. But if you do, you’ll do so until nothing fits, not even the chair.

Getting there: there are flights to Barcelona from most main UK airports. Airlines serving the city include: British Airways (0870 850 9850, www.ba.com), Clickair (www.clickair.com), EasyJet (www.easyjet.com) and Jet2 (www.jet2.com). Aer Lingus (0818 365000, www.aerlingus.com) flies to Barcelona from Dublin and Cork.

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