What four-letter English word is a name for a public open-air swimming pool?

Wow! Now I understand why Lido Beach in Johor Bahru, Malaysia (my hometown) was named! thank you! ❤️

The one in the picture is in Plymouth.

Large yahts and cruise ships may have a Lido Deck with an open air pool (or pools).

I've not been to lido

Thank you. Clay, That makes sense now!