From the top of Corfu fort, I could see figures kicking in the emerald water. Determined to join them under the sweltering sun, I walked round the fortifications seeking only to go down. The beach was grassy, rocky, no sand in sight, with sleek yachts clinking against each other in the marina next door. I walked out along a low stone boundary to climb down a rusting ladder into the water, timing my push off to avoid the swell of the waves pushing me back into the rungs.

The cool was delicious against the unforgiving sun that beat down onto rock, turning sand stone into blaring white. The water out here at the end of the wall was deep and turquoise, rocks of chocolate a few feet under the surface. Boats passed by, their wake causing the water’s surface to rise and roll like a wave pool.

The voices on the shore spoke a mixture of languages. The hot sun was bearable under the water – painting dazzling specks on the surface, glittering, always shifting, constant never. There were dark rocks at the base of the fort and a doorway half way up the wall that lead straight out from the fortifications into midair, with water and rocks below.

When I get back to the bank a huge bee is investigating my clothes. I wait for it to get bored, not shivering like I would at home because even on a wet body, the air is warm. Corfu’s crystal clear water is striped with incredible colours, deep blue, turquoise, vivid green, lilac. Just sitting and watching it is almost enough…..but being in it is better!

I’m raising money for the Alzheimer’s Society. Please sponsor me at http://www.justgiving.com/swimbonnieswim