Karavostasi beach
Not the sandiest beach....
....but quieter and visited by locals. A great place to be later in the day, and we enjoyed early evening at the friendly Maria's Kantina on the beach. Small and simple menu, but we enjoyed a tasty and satisfying meal of souvlaki, salad, bread and hand-cut chips overlooking the lovely view. Lovely village wine, and such a reasonable bill. Not to be missed if you're staying in Istron. Bravo, Maria!
Beach Agíou Panteleímonos
A Sunny, Sandy, Hidden Gem
Agios Panteleimonas Beach is not exactly a secret, but it gets a lot less hype than many Cretan beaches that are not nearly as nice. Situated right next to a ruined Minoan Port, the beach is usually less crowded than its neighbors, and very easy to get to. There's also the picturesque Ekklisia Agios Panteleimon church, and ample souvenier and eating spots here too.
If you are anywhere near, give this beach and nearby Voulisma Beach (150 meters east) a try. You can't go wrong.
Istro Municipal Beach
A small beach that is 300meters after Voulisma beach, in the same bay, It is more quite except August that is more crowed and still one of my favorite!