Playa de Muro picks up where Playa de Alcudia leaves off, running south through the municipality of Muro toward Ca'n Picafort. There's no obvious dividing line in the sand, but the character of the beach changes noticeably: the crowds thin, the dunes appear, and behind the beach the first pine trees signal the edge of the S'Albufera reserve. Parts of this stretch have been designated a protected natural area, which limits the development that's allowed behind it.
The sand here is the same quality as the main beach but the facilities are fewer — sunbed rentals and a smaller number of beach bars, with long stretches of beach that are essentially wild. The water is equally shallow and clear. In July and August it's still busy, but "busy" here means you can walk a hundred metres and have some space. In May and September it's genuinely tranquil.
Playa de Muro is better reached by bike than by foot from Puerto de Alcudia — the distance is far enough that cycling the flat coastal road makes more sense than walking. A bike path runs most of the way, and rental shops in the resort can set you up for a half-day or full day at very reasonable rates.