If you're looking for a quiet, relaxing place to sunbathe or just spend some time by the water, Carreiro de Joanes is a great option.
It's a small beach that's protected from the predominant wind in Peniche.
This beach is great for families with small children. There are plenty of rocks for the kids to explore, and the crabs, limpets, and other marine life add to the fun. Teenagers might find the rocks a bit of a turn-off, but for adults, this is a great place to relax and enjoy the sun.
I personally love it here. At low tide, the beach forms a natural pool that is perfect for a dip.