Monolithos beach is on the east coast of Santorini
close to the northern end of the airport. It's about 5km from the islands capital and that'll take roughly 10 minutes in the car.
The beach is a good size, it's around 100m deep at it's widest but tapers down to less than 20m at it's narrowest. There's a small collection of sun loungers, generally down by the marina and the rest of the 1.5km stretch is left clear.
Monolithos has crystal clear waters with fine black sand. The water gently shelves in to the sea here so it’s great for children. Just keep in mind that the location of Monolithos beach means it can get windy in the summer months so it's best to go on a calmer day, especially with little ones.
Monolithos beach has plenty of facilities including some good tavernas serving food and drink, some umbrellas and sun loungers are available to hire and even a kids playground, football pitch, basketball hoops and a volleyball court but no water sports.
You also get great views of the planes coming in to land here as Monolithos is close to the airport runway.