Leave the M25 at Junction 20. Turn left on the A41, signposted Aylesbury and Hemel Hempstead. After 14 miles take the exit signposted Wendover B4009 and Dunstable B488. At the roundabout go right (Dunstable B488), over the A41 and straight on at the next roundabout. Follow the B488 for 2 miles to the next roundabout. Turn left, signposted Long Marston and The Reservoirs. In 1 mile turn right at the next roundabout on the B489 towards Ivinghoe and Marsworth. The White Lion is on your left in ½ mile, just before the canal bridge. Park in the pub car park.
The journey from J20 is approx 17 miles.
This walk is an “easy-going waterside ramble” (it says in the book). No hills, no stiles and fairly good paths throughout. If you are very early the café over the road is open from 10am for coffee.