For the first time that night, I woke up alone. My home for the night was a small dry cave, entered from above, where I had slept on a bed of bracken. Dinner had been a mug of heather tea, fresh from the hillside. I cooked the tea on a fire which I made from sticks and driftwood.

From the mouth of my cave I could see the greens and browns of the hillside, and the blue Atlantic Ocean beyond, with the other islands of the Inner Hebrides. I had survived alone on my island for 18 hours, without taking any food or drink with me from base. I had a strange mixture of feelings - quite proud of myself, but uncomfortable from midge bites and a bump on the head.

Once I got back to base I found out how the others had got on. Everyone else had “survived” in groups of three or four, some going further away on to other islands joined up at low tide. Some had tried to kill a rabbit for food; others had eaten plants, berries and even shellfish, as we had been taught on the overnight expedition earlier in the week. All were glad to get back to normal food with a hot cooked breakfast.

Rua Fiola is a small, private island belonging to the Johnson-Ferguson family, who have built a timber cabin there as the base of an Exploration Centre. The whole family were there, including the three children. Torquil, the father, farms in the winter and runs holidays for groups of about 35 people aged 9 to 17 in the summer. My friend Jonathan and I went last July when I was 13; there was also a group of about 20 from Gresham’s School in Norfolk.

Rua Fiola is an ideal spot because it’s near to Oban, so it was easy to get there by rail up the West Highland line from Glasgow. You can’t see any other man-made structure for miles and miles except Cullipool (a small fishing village). There is no electricity on the island: we used oil lamps and cooked on bottled gas in the house.

Despite there being no television, there was masses to do and see. During my stay I did all the outdoor activities you can imagine - canoeing, climbing, abseiling, fishing, not to mention the survival skills we needed for our overnight adventure. Any time you wanted, you could go on a giant swing or a trampoline or a small assault course. At the end of the week, we all went on a huge flying fox from the cliff top to the base, ending up in a giant mud bath where treasure is supposed to be buried.

Because the island is so remote, you are always seeing interesting wildlife. During my week I saw lots or cormorants and shags, and sea otters swimming in the distance. We also saw seals basking on the rocks, and the boat got so close you could have leaned out and almost touched them.

The instruction was the best I have ever found at such a centre. It’s much more adventurous than the average activity holiday, and more fun than a Scout holiday. Everyone was very safety-minded, and they had all the right gear, which made me a little less unhappy about dangling mid-air 50 feet above hard, rocky ground.

Torquil met us off the train at Oban. From there transport to and from the island is by two jet boats called Eider and Sulaire. The main boat drivers - Big Al and John - are very good indeed, and if you ask nicely they might even let you have a go. One afternoon, Big Al saw a strange fishing boat on the waters and went over to investigate. It turned out that the strangers were up to no good, so we saw them off.

Looking back on my week there, I learned lots of new skills and I got on well with the other young people. However, the main thing I learned was to rely on myself, and that I could survive alone in the wild in Scotland. It was unforgettable.

Details from Wild Island Exploration, Solwaybank, Canonbie, Dumfriesshire DG14 OXS. Tel: 0138 373 2240 Sandy Bloomer is a pupil at Dunblane High School