Even under the water, Alassio is unique, with its white sand reminding one of tropical beaches.
Its large sandy beach reaching 50 meters in width at various points is as long as the town, following the coast, forming a large protected shallow depth gulf for hundreds of meters.
It is the Bay of Alassio, large and sandy and without currents. At the centre of the town, perpendicularly to the coast, there is a long landing-stage with, at its extremity, a depth of only 3 metres, frequented by huge shoals of grey mullets and isolated striped breams.
If we carry on westward, we reach the promontory of Capo Santa Croce behind which is the tourist port of Alassio. The most interesting depths for those wanting to admire a varied and colourful underwater environment, start after the harbour, particularly around Punta Murena. Parallel to the coast, a number of reefs are scattered as far as to the town border with Albenga. Here even under a few metres of water fishes of various types, shellfish, Gastropods, Cephalopods and Lammelibrancs can be seen. There are multicoloured rainbow rasse, scorpion fish camouflaged among the rocks, octopus and even the ever suspicious cuttlefish.
But one can run into white breams, particularly after a heavy sea, as well as into some giltheads.
Swimming towards the open sea, the sand is interrupted by majestic prairies of posidonia, where corvines hide. 
Shells of various types can be found on the sand, particularly murexes.

Reaching Capo Lena, low and stony because of the debris brought by the River Centa, the depth does not present any attractions for underwater diving, except when the northern wind blows and the water clears. In this case one can run into some big bass attracted by the brackish water. 
Off the Gallinara Island, to be admired only from the surface, since swimming and diving is forbidden, about 500 metres to the East of the Island there is a wonderful wreck, the merchant ship Umberto I lying on the sand about 50 metres down.
Finally, just in front of Albenga there is one of the most interesting archeological areas in Italy. In the area centered at 44° 03N.8° 15E some decades ago was found the wreck of a Roman ship carrying thousands of amphoras, therefore in this area and within a range of 300 metres, fishing, anchoring and diving are forbidden.