Oran’s coastline is mostly cliffs with some tiny sandy parts in between. But if you drive about an hour west (depending on traffic it can be faster or take a lot longer), you’ll eventually reach a zone of beaches reaching from Ain Turk via Cape Falcon to Les Andalouses.
All those beaches are extremely popular during summer. When we went there a handful of days ago however, the one we had picked was almost empty. The stroll we took was very pleasant, the food we had afterwards mostly too. It’s just so annoying that when you order vegetarian food (no fish, no meat) you still find chicken sprinkled over your salad – it’s not considered meat!
And a tip regarding transport: there are buses during summer to and from Oran. If you come by taxi, arrange with your driver beforehand to take you back. If you’ve got your own transport, parking is likely to be a problem during summer.