A connected series of routes around the west and north of London, many of them waterside. The River Thames Flood Relief Channel (or Jubilee River) and Grand Union Canal make up the bulk of the western half, with railway paths continuing the ride between St Albans, Welwyn Garden City, and Hertford. Less than a quarter of the route is on-road, though the proximity of the capital means these sections can be busy. Several sections are unpaved but nothing that should trouble moderately robust tyres.