I think the 'Neom' project in Saudi Arabia proposed designing a huge dome over the ocean where sun light heated the water and it condensed on the walls of the dome where it was collected. I wasn't sure if this was a real project or just theoretical. In looking at the website it appears they have dropped this idea for something more conventional. https://www.neom.com/en-us/sectors/water/infrastructure

I've seen some theoretical projects at scale, but I guess never a real one.

I live in San Francisco, and I always think when I see the fog roll in it would be great to devise a process for capturing it. Seems very do-able on a building scale, but perhaps never attempted at the city scale.