Monkstone Beach is situated south of Monkstone Point, which is roughly midway between Saundersfoot and Tenby. Roadside parking (free) is available on the lane to Trevayne Farm camping site, from where a permissive path continues through the farm to the coastal path. From here, one path (straight ahead) leads out to the headland where it's possible to scramble (with some difficulty) down to the shore, but the easiest access from this junction is a well-maintained steep path with over 190 steps which descends the wooded cliffs.
The beach is mostly fine sand backed by a storm bank of pebbles. During the high tide period most of the sand is covered, but this is an ideal beach for sea swimming at this time, and the rocks near the headland are popular for diving and jumping. Between low and mid-tide, the southern end of the beach becomes accessible, and is rockier, with streams, rock-pools and a waterfall where a small stream drops onto the shore. The cliffs here are of shale and sandstones and are very unstable. Access to the coastal path is possible by walking up a steep rock slab. Only on the very low spring tides is it possible to proceed further along the shore towards Tenby. In the opposite direction it's possible to walk to Saundersfoot along the shore at low tide, the critical cut-off point being just the other side of the headland.
There are no facilities at the beach, but Trevayne Farm has a small shop selling local produce and ice-cream. It's an ideal beach for families seeking a quieter, more rural beach than Saundersfoot or Tenby, and dogs are allowed at all times.