This is a photograph of the intersection of Holywell Lane and Curtain Road in Shoreditch, London. This location is where the Walbrook began in medieval London before it went onwards to Moorfields and down to the River Thames.
This is a map of the City of London in 1300. This map demonstrates that the Walbrook begins a bit before Moorfields, extends throughout the middle of the City, and empties into the River Thames at Dowgate.
This map depicts the west half of London in 1270. The River Fleet can be seen running west of the city wall until it eventually meets the Thames. Fleet Bridge, Fleet Prison, and Fleet Street are also depicted on the map.
The Fleet begins from two streams located on Hampstead Heath, one of which begins in the grounds of the Kenwood Estate. Both streams were dammed in the eighteenth century to create reservoirs. These reservoirs then run into underground sewers and…