We call them house martins now but traditionally they must have been cliff nesters. There used to be a good cliff nesting colony at Howick in Northumberland but these disappeared some years ago now. So, wandering the northernmost coastline of England just to the north of Berwick upon Tweed I was pleased to come across a colony that I had not seen before.
According to the RSPB, these birds began using buildings in the 19th century and as we built more and more, traditional nest sites became 'all but abandoned' in the early 1900s.
Whilst it is great to have a colony on your house, the birds seem more appropriate on a wild sea cliff winging it with the fulmars.
The Berwick colony uses a wonderfully wind-sculpted cliff on which the nests are all but invisible. Click the photo and play spot the nests.