From Harrow-on-the-Hill Underground Station Tube to Northwood Underground Station. 9 min £2. From Harrow Bus Station bus to Northwood Hills, Hallowell Road. 24 min £2. From Harrow on the Hill taxi to Northwood. 8 min £21. From Harrow on the Hill Uber to Northwood. 8 min £11. From Harrow on the Hill walk to Northwood. 1 h 30 min.