BARCELONA is one of the world’s greatest cities — and its marathon, or marató, is one of the most challenging and colourful.

The 26.2-mile circular course is studded with famous landmarks, the organisation is highly efficient and the enthusiastic tens of thousands who line the streets really get behind the event.

Like all continental marathons, it is measured in 42.2 kilometres.

The first 10k is undulating, and there are many other inclines including a longish one towards the end.

My usual plan is to aim for five-minute kilometres to finish in around three hours 30 minutes.

This time, however, was different because I strained my left calf in January and lost a lot of training.

The pain flared up again two weeks before the race when I over-optimistically started a 16-mile run too quickly.

So my aim was to take it nice and easy by adding about 30 seconds to each kilometre in the hope that the calf would behave itself and I could finish between 3.45 and four hours.

However, I began the race not knowing if I would be able to finish, which didn’t fill me with an abundance of confidence.

This was my 42nd marathon, third in Spain and first in Barcelona, the capital of Catalonia.

I lined up with 19,200 others for the 8.30am sortida, or start, on the Avinguda de La Reina Maria Cristina, which leads out between two imposing 47-metre high Venetian Towers to the Plaça d’Espanya.

It was heavy rain the day before, but race day was beautifully sunny, about 8oC (46F) with an occasional, slightly chilly breeze.

The starting area is overlooked by the majestic National Museum of Art high on Montjuïc hill, at the foot of which lies the Magic Fountain, or Font Màgica.

More fountains run up each side of the street and crowds occupied every available space. Great music, including Chariots of Fire, blasted out. A truly inspiring atmosphere!

The race was started in phases to ease congestion. Each one related to the colour of vest numbers, based on predicted time.

Blowing machines sent out thousands of pieces of different coloured confetti-like paper for each start. I was in the second section, which saw blue shapes exploding skywards. A nice touch which added to the festivities.

Freddie Mercury singing Barcelona (of course!) sent us on our way north-west to the first target at 6k — the mighty Nou Camp stadium of Barcelona FC.

A guard at the gate watched us streaming past, but the world famous players were ‘Messi-ng’.

Onwards and upwards and downwards we went, getting welcome shade from the sun on the long avenues heading east. Catalan architect Antonio Gaudi’s La Pedrera (the stone quarry) apartment building appeared at 14k, followed soon after by his cathedral masterpiece Sagrada Familia, both of which are Unesco World Heritage sites.

I craned my neck to try to see the top of Sagrada as we ran by. It soars Heavenward on a massive scale. Construction started in 1882 and is due to be completed in 2026, the centenary of Gaudi’s death. Lots of bands kept the runners entertained as we went north-east to eventually reach 20k and turn south towards the beach, the sparkling Mediterranean and the Port Olimpic, which hosted the sailing events for the 1992 summer Olympics.

North we went again at 35k up the side of the Parc de la Ciutadella, which includes the zoo, and through the Arc de Triomf, built as the main access gate for the 1888 Barcelona World Fair.

My troublesome calf was still faring okay, but my back was starting to feel the effect of having to ratchet up distances in double-quick time after I got back into training in mid-February.

Increasing the mileage in a posthaste fashion you won’t find in any coaching guide was a calculated gamble that could have back-fired, but looked as if it would pay off.

Another kilometre north-west took us to the Plaça de Catalunya, regarded as the centre of this vibrant city of 1.6 million, and then we went south again to the 60 metre tall monument to Italian explorer Christopher Columbus, overlooking the port at the lower end of popular tourist street La Rambla.

The final two kilometres beckoned north up Avinguda Paral·lel on a steady incline towards the arribada, or finish, back where we started.

Plaça d’Espanya loomed ahead, and I reeled it in slowly before turning left on to La Reina Maria Cristina for the finishing straight of around 200 metres through the towers.

Booming, electrifying music, huge cheering crowds, spouting fountains and the background of Montjuïc made this one of the most exciting marathon finales I’ve ever taken part in.

My delighted and relieved grin was as broad as the street as, arms aloft, I crossed the line in 3-47-21 in 6,075th place.

Bravo Barcelona!