Cleopatra's beach is both the most beautiful of Marsa Matruh, perhaps all of Egypt, but it offers bad chances of swimming. If you take your chance you better be a good swimmer, and fight your way out between the weird-looking cliffs here. There are good chances that waves and currents become hostile. But it is a fine place to relax, perhaps even sun-bathe, as long as you don't mind few possibilities of cooling down in the sea.