After 26 gruelling miles I was proud on Sunday to finish my first marathon.

I can only say it was a surreal experience. Having flogged round the Surrey Hills in Hascombe, Hambledon and along the River Wey I was ready for some pain.

Indeed the most I did in training was 20 miles.

But – for me at least – the ‘wall’ did not really materialise because I was just overwhelmed with the amazing crowds who carried us forward.

I don’t think there was any part of the entire course where there weren’t people, often on both sides of the road and sometimes six rows deep, cheering on the over 40,000 runners.

The London Marathon is thought to be the best in the world – and I can now see why.

Every year we recreate a mini-version of the crowds that come out for a Jubilee, the Olympics or (more sadly of late) a Royal funeral – and always with the same goodwill, generosity and trademark good humour for which we are so well-known.

We drank the Lucozade and Buxton mineral water provided by sponsors but spectators bought along chopped oranges, Indian sweets and other delights.

There were placards to keep our spirits up including ‘Remember pain is just the French word for bread’, the odd political dig such as ‘Thanks for showing the government how to run things’ and one or two thoughtful ones such as ‘I have faith in complete strangers like you!’

On corner after corner there were steel bands, jazz orchestras, DJs pumping out tracks and even a Rock Choir (thank you Farnham) to keep us motivated.

All as we ran past iconic landmarks such as the Cutty Sark, Canary Wharf, the London Eye, Big Ben and Buckingham Palace.

My only sadness was that the crowds were not there to cheer me on when I woke up this morning with rather sore feet – but I am not complaining.

It was an exhilarating once in a lifetime experience and I found myself enjoying pretty much every minute of it.

As Herald readers know I was running with my brother Charlie who is fighting off a horrible cancer.

He had pain in his right foot which meant we stopped every mile or so to allow it to recover.

He never had anything but an enormous grin on his face and I have never been prouder of him than I was then as he literally ran through what must have been excruciating agony.

Between us we raised over £40,000 for the Royal Surrey’s new Cancer Centre and Sarcoma UK so a massive thank you to everyone who supported us on a day that will live with me forever.