Not to be missed:

Kommos Beach: with fine golden sand and framed by natural dunes, this nudist beach is situated at the western part after Kalamaki. It stretches over 2 km along the south coast west of Matala and is up to 40 m wide.
Kalamaki Beach: nice sandy beach with free umbrellas & sunbeds in Kalamaki 70200, Greece
Preveli Crete Beach and Palm Lagoon where the Kourtaliotis River meets the sea with palm groves: located @ 5F3F+2G Preveli, 74060-Foinikas, GR
Vai Palmgrove at the north-eastern edge of the island {2 hours drive from our apartment}
also check out multiple other recommendations