The river crosses beneath the A1M close to the Roman baths, then beneath the Hertford Road and then Bessemer Road that leads into Welwyn Garden City. The narrow lane Digswell Park Road cuts a diagonal over the river and across an area of water meadow once containing fish ponds. Next to it is a farm with its land encircled by the bigger roads. Visible from the railway but not from ground level is Digswell Lake, fed by the Mimram, and now a nature reserve.
The Digswell viaduct is a feat of engineering beneath which the Mimram sidles on its way to the mill at Digswell, a hamlet now sandwiched between the well-to-do housing of Welwyn North and the Haldens district of Welwyn Garden City. The ancient Maran House there recalls one of the old, alternative names of the Mimram.