Complex sentence: Before the 1870's St Philip's churchyard was surrounded with Georgian terraces, however as a result of the Second Birmingham Improvement Act of 1861 the buildings were to be cleared for the redevelopment of Colmore Row.
Split into simpler sentences: Before the 1870s, St Philip's churchyard was surrounded with Georgian terraces. However, as a result of the Second Birmingham Improvement Act of 1861, the buildings were to be cleared for the redevelopment of Colmore Row.