4 miles (6.5km)Once the River Lea had enough water just beyond the source to drive a mill. But this first stretch into Luton is remarkably rural, with rare plants and the possibility of seeing a kingfisher. The first pub on the river is Bedfordshire’s oldest building. The beginning of the Lea Valley Walk follows the Icknield Way Trail, a 105 mile regional route based closely on the line of Britain’s oldest road running from Wiltshire to Norfolk.RefreshmentsLeagrave’s Three Horseshoes Roundabout: McDonald’s. Open all day.Biscot: Old Moat House, Nunnery Lane, Biscot. Mon–Fri 12–2.30pm and 5.30–11pm; Sat and Sun open all day.Luton: Cafés in shopping centre and town. AccommodationLuton: Premier Travel Inn (The Brache), Osborne Road LU1 3HJ (01582 421900). On Walk near southern edge of town in Section 2.TransportLeagrave: National Rail.Luton: National Rail.Tourist InformationLuton: Luton Central Library, St George’s Square (01582 401579).MapOS Explorer 193 (Luton & Stevenage).