The beach

Glysteri Beach is a small, beautiful pebble beach with a footbridge from which you can jump into the water.  The beach is great and very beautiful.

Parking

There is a maintained parking, a beach bar, and sun beds. You can leave your car only in the parking because the place is something like private property, and you will have to pay for your parking and for staying on the beach. You can choose how to pay for it, for example, you can buy a coffee in the beach bar or rent a sunbed for your stay but you will have to pay something. Sunbeds may be reserved in the summer, so if you want a sunbed, book it in advance. 
If talking about water there, they are taking good care of the beach, but if you swim closer to buoys and nets and behind them, you will find the water pretty dirty and full of rubbish.
Undoubtedly, the surroundings are very beautiful. You can even find cliffs nearby to jump into the water further from the beach.

Mamma Mia

If talking about the Mamma Mia movie, then they filmed the arrival of Donna’s friends at this beach and jumping in the water from the cliffs when Sophie sailed with her potential fathers.