Mahahual's beach runs along a narrow malecón of small restaurants, dive shops, and beach clubs. The reef takes the edge off the Caribbean swell, so the water is usually gentle enough for swimming and lazy snorkelling close to shore.
Come early if a cruise ship is in port; by midday the beach chairs and massage tables can make the front feel busy. On non-cruise days it is much easier to see the old fishing-village scale of the place.