The Blue Lagoon takes its colour from the seabed, not the sea. A floor of pale limestone sand, ground fine by the waves, throws sunlight back up through only a few metres of water. The channel between Comino and the uninhabited islet of Cominotto turns an electric turquoise so bright that moored boats seem to hang above it rather than float. You wade in from a thin strip of sand, and by late August the water is bath-warm: a shallow, sheltered channel heats faster than open sea, and it still holds 23-24°C through October. Swim the short crossing to Cominotto, drop off the low limestone ledges, or stand waist-deep and watch your own shadow travel across the bright floor.
Comino itself is 3.5 square kilometres of low garrigue with two permanent residents, named after the cumin that once grew wild on it. Corsairs sheltered in its caves, and the island later served as a place of quarantine and exile. Saint Mary's Tower has watched the channel from 80 metres up since 1618. Above the shore the garrigue flushes purple with wild thyme in May and June, the plant behind Maltese honey. The whole island is a bird sanctuary and a Natura 2000 site, so hunting and trapping are banned here all year. The crowds are the catch. Since May 2025 every visitor arriving by boat must pre-book a free slot, one of three a day. Numbers are capped at 4,000 people at a time and checked with a QR code and a wristband at the landing. In winter the day-boats stop, the visitors disappear, and the two residents have the lagoon to themselves again.