From London Bridge terminal, it takes around 15 minutes on foot to get to St Paul's Sanctuary

https://sgp1.digitaloceanspaces.com/travelling-to-st-paul-cathedral/uncategorized/all-aboard-the-best-courses-from-londons-train-stations-to-st-pauls.html

From London Bridge station, it takes around 15 minutes on foot to get to St Paul's Basilica, going by renowned landmarks along the road