Handbag, I used to walk with my twin to Bidston from Wallasey over sixty years ago and passed the Triangle. I think it was near the footpath over Bidston Moss between the Wallasey Tech School bottom of Mosslands Drive and where M53 flyover was built. We used to go to Bidston Hill
and were annoyed the flyover spoilt our exploring. It is a pity young people don't have the freedom we had, as today parents are more aware of strangers than in a more innocent times.
My brother used to do school cross country running on that route. He loathed it and would go halfway then have a rest and go back to school. It was obvious that sport was not his forte.