B IG PI C T U R E Tulum, Quintana Roo, Mexico This photograph was taken last year during Cave Camp, an annual cave diving event in Tulum. I was at Cenote Xulo, one of my favourite dive sites — after a small entrance, the cave opens up into this incredible chamber of stalactites. I wanted to emphasise the ceiling, so I used a fisheye lens and angled the camera upwards to achieve this exaggerated perspective. These caves are facing increasing pressure from development, with the government now planning to build a rail network through this area. I hope this image can raise awareness about the beauty and fragility of these sites. TOM ST GEORGE • PHOTOGRAPHER