A world heritage site, Westminster Abbey is a collegiate church and 'royal peculiar', responsible to the monarch rather than a bishop. Built and added to over a number of centuries, largely between 1245-1517 and again with towers built by Nicholas Hawksmoor in the 18th century, this church may not be the most impressive in terms of architecture, but as the burial place for English kings (starting with Edward the Confessor) and other worthies, it has important historic significance.