Complex sentence: The park covers three hectares, and was created in 1985 on the site of a gas works (demolished in 1960); the ornamental rail bridge, used to carry coal from the main line across the River Thames to the works, still stands.
Split into simpler sentences: The park covers three hectares, and was created in 1985 on the site of a gas works which was demolished in 1960. The ornamental rail bridge, used to carry coal from the main line across the River Thames to the works, still stands.