What is the best beach in Krabi?

Phra Nang Cave Beach. It's at the southern tip of the Railay peninsula, a five-minute walk from Railay West, and it's a noticeably better beach: smaller and more sheltered, with water that shifts between green and clear blue, and limestone cliffs that rise directly from the sand at both ends rather than framing it from a distance.

The cave at the far end of the beach is a fertility shrine, filled with wooden offerings left for the spirit said to live there. It's one of those genuinely specific and strange things that stays with you.

The honest problem with Phra Nang

It gets crowded. The 4 Islands tours stop here, and there are periods in the middle of the day when it has too many people in it. The way to see it at its best is to be on Railay the night before (or take the very first longtail from Ao Nang in the morning) and get to Phra Nang before the day-trippers arrive. Late afternoon, once the boat tours have moved on, is the other good window.

The second-best answer

If Phra Nang is packed, and you want more space, Railay West is the better fallback. It's longer and more open, the water is calm, and the afternoon light on the cliffs is good. It's the beach most people picture when they think of Krabi.

What about Klong Muang or Koh Lanta?

Klong Muang, north of Ao Nang, has a long quiet beach that rarely gets crowded and is good if you want space. The trade-off is that there's less to do nearby. Koh Lanta's west-coast beaches are similar: long, less crowded than Ao Nang or Railay, and better suited to people who want to sit still for a few days rather than base themselves for day trips.

For the full picture of getting to Railay and what else is there, see the Railay Beach guide.