Private Andrew Swanwick faced up to 59 mortar salvoes in a single day as his small platoon defended high ground in Helmand Province, Afghanistan.

The 21-year-old, a machine gunner with Z Company of the Princess of Wales' Royal Regiment 2 Battalion, was defending a space the size of a tennis court from 400 insurgents launching attacks from a lush valley below.

The platoon's resistance stopped the Taliban taking up important positions above the town of Musa Qala.

Back at his Lee-on-the-Solent home, Pte Swanwick said: 'I was just doing my job, but it was tougher than anything I've done before.

'I wanted to tell my family what was happening, but it would have been too hard for them.'

Pte Swanwick and his platoon of about two dozen men were encamped by the Roshan Tower, a disused mobile phone mast that marks the northernmost base of the coalition forces.

If it were to fall into Taliban hands, it would cost British troops months of hard work and dozens of miles in territory.

Pte Swanwick said: 'You know you're right on the frontier there, and the Taliban know exactly where you are. We have interpreters who tell us what they're talking about on the radio, so you know when a hit is coming.

'It makes you really nervous because they were concealed below us and we couldn't sight them properly. All you can do is wait for their fire and then respond as fast as you can.'

As the company machine gunner, Pte Swanwick was perched at the front of the tower defences, exposed to mortar and rocket-propelled grenade fire.

'It takes us time to get our sights on them and all the while they are firing the mortars,' he said. 'You hear the crack in the distance and then have to take cover, because their fire was always pretty accurate. We have pretty basic protection so when the explosions start it's obviously worrying.'

With air cover needed at other sites across Afghanistan, on one day the base took 59 mortar hits without relief. 'As the day wore on we were getting really tired, and they were relentless,' he said.

'We could track the mortars as they got closer and closer. Knowing there's no air cover gets you down. It was a real relief when it ended.'

By the time he returned to Forward Operating Base Edinburgh the Taliban had scaled down their attacks.

He said: 'It was a great feeling thinking we had done our job and kept the area safe, it was really tough and it was great to come out of there.

'I'm glad I did my duty. There are sergeant majors training us who have never come up against that so we can look back with pride.'