After the Great Fire of London in 1666 there were swathes of land in the City of London west of Pudding Lane (where it started and got blown out of control by an easterly wind).
The Lord Mayor (a Yorkshireman by the name of Sir William Turner, from Kirkleatham Hall) and the aldermen (City dignitaries) were in a dilemma. There were all these survivors and no churches for them to go to to thank their maker for surviving both the Plague AND the fire. They were forced to live in tents around the Inns of Court at the City's edge. And, (the big AND) the City had lost its cathedral, Saint Paul's.
Enter a reasonably well-known architect by the name of Christopher Wren (he wasn't knighted then yet).
Look for all these City churches on Wikipedia as far west as St Clement Danes on the Strand and Bride's (short for Bridget) behind Bridge Street and Fleet Street. They look like wedding cakes, really, but the Lord Mayor and his aldermen were happy. Plans were also submitted by Wren for the re-drawing of the City's streets, but they were rejected on the grounds that they had little to do with property boundaries. The big test was designing St Paul's. His original was in the shape of a Greek cross, each side of equal length, but that wasn't on. There had to be a compromise between that an the Gothic idea of the 'long (Roman) cross'. The design was given a 'tweak' or two as it went to and fro from the planning committee back to Christopher and back again...
Still, what you have is the 'perfect English classical church' at the top of Ludgate Hill, backing on to Watling Street and Cheapside in the east. Asked why there wasn't a memorial to Wren, a tourist was pointed by one of the canons to the plaque on Wren's tomb that tells:
'Reader, if you seek his monument, look around you'.