have just come across your post, trimdon street was a very small st on the corner of a busy junction on middleton road , which led to the docks and the swing bridge, it was there on the 1896 ordnance survey map, when the houses were demolished as you said it was in the early 1970s, and my family moved into the new houses they built on the site in 1974, there was at that time a laundry on the corner, which my mother used for years before we moved in to the area, they collected your washing and then delivered it back all done. If you go onto amazon or play.com they may have some books by a guy called george colley he wrote lots of books about hartlepools past all in photos, they are a marvelous insight in hartlepools history, i was looking at one yesterday in the library, i found photo of a street i was looking for in one of them , so well worth a look. sue