There is not a great deal to do in Marsaxlokk — the village itself, the working harbour with its painted luzzu boats, and the famous Sunday market are most of the pleasure. Plan a long lunch on the waterfront and a walk on the Delimara peninsula out to St Peter's Pool, the open-rock swimming spot ten minutes' drive south. Together that makes a full and satisfying day out.
If you want more, the prehistoric Ġgantija-era cult site at Tas-Silġ on the hill north of the village is open to the public on selected days; the Għar Dalam cave at Birżebbuġa, a couple of kilometres west, contains the fossils of dwarf elephants and hippopotami from the last Ice Age.