Complex sentence: Since 1972, the public entrance is through the Coopers'Hall, the earliest surviving building on the site, having been built in 1744 for the Coopers' Company, the guild of coopers in Bristol, by architect William Halfpenny.
Split into simpler sentences: Since 1972, the public entrance has been through the Coopers'Hall, the earliest surviving building on the site. The Coopers' Hall was built in 1744 for the Coopers' Company, the guild of coopers in Bristol, by architect William Halfpenny.