The heritage site Explore Churches has shown where the churches are along the route.
St John's the Evangelist church in Blackheath is first on the list, who cancelled their morning services and provided breakfast from 9-11am
They are followed by the Roman Catholic church Our Lady of Grace in Charlton and St Mary Magdalene Crescent Church in Woolwich at miles two and four.
Also in Charlton, St Luke's church bells played the theme Chariots of Fire as clergy blessed runners with holy water.
Bunting was put up at mile six outside Christ Church Greenwich, a contemporary Church of England gathering, who had an early morning service at 8:45 and then went to sell breakfast rolls to supporters to raise money for their local night shelter.
The church where Henry VIII was baptised comes into view at mile seven. St Alfege in Greenwich is currently being refurbished with money from the National Lottery Fund to conserve its heritage for visitors.
Mile 7: St Alfege, Greenwich— Explore Churches (@ExploreChurches) April 25, 2019
Coming down the long straight of Mile 7 be spurred on by the magnificent site of the white tower of St Alfege. Henry VIII was baptised here in 1491. After enjoying the green space of the Naval College runners pass Cutty Sark.https://t.co/SnMkMF0oGQ pic.twitter.com/L9Oq4YxcKp
St Paul's Deptford is next, followed by Holy Trinity Rotherhithe, who have moved their Holy Communion to 5pm.
A few miles and a few churches later, the race reaches St Peter's Barge church which floats on Canary Wharf and then All Hallows Church by thr Tower of London, who hosted the official London Marathon service on Saturday and were open all day on Sunday.
We're all set for the #LondonMarathon at #mile23 Come and gather with runners, suppporters, organisers and charities on Saturday at 6pm for our special Marathon service #pray #LondonIsOpen #citychurches @dioceseoflondon @christian_aid @LondonMarathon pic.twitter.com/ZveftMKY3X— AllHallowsbytheTower (@AllHallowsTower) April 26, 2019
After the race passes through the financial district, St Benet's Welsh church and St Paul's Cathedral, its ecclesiastical finish is Westminster Abbey, before runners finish on the Mall leading up to Buckigham Palace.
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