This is a vintage picture of the lighthouses and road tunnel of Monte-Carlo or Monaco which was probably taken about 1960.
This is part of a collection of medium format colour slides I acquired a couple of days ago which I’ve been sorting through. I wasn’t sure of the location at first, and then on closer inspection I realised that the road which is visible on the left-hand side of the picture is going into a tunnel, and I wondered if it could be the location of the Monte-Carlo grand Prix? A quick search in google images confirmed that this is the location, although there have been many changes since this picture was taken. For example, the tunnel the road disappears into is now a hotel and the lighthouses on the ends of the sea wall have been removed while the walls were remodelled in 2005.
I’ve put the date at 1960 because the slides in the series with this picture are generally in the same date range and I suspect this picture was taken at the same time.