Complex sentence: The playing fields first opened in Bishopbriggs in 1923 are still owned by the Allan Glen's School Club and are the home ground of Allan Glen's RFC, who currently play in the West Regional League Division 1.
Split into simpler sentences: The playing fields first opened at Bishopbriggs in 1923 and are still owned by the Allan Glen's School Club. They provide the home ground for Allan Glen's Rugby Football Club, which currently plays in the West Regional League Division 1.