Park in the small car park near the Bionnay Chapel.
(S/E) Head towards the chapel and take the tarmac road leading uphill to the right. Pass the first hairpin bend.
(1) Quickly take a path that climbs steeply to the left.
(2) When you emerge at the hamlet of Montivon, head right to pass in front of the chapel. Facing the chapel, turn left onto the path – which remains steep – heading due north. Cross the TMB route and reach the crossroads in the hamlet of Champlet.
(3) Take the forest track on the right, which now climbs more gently. Cross the TMB route again and reach a junction.
(4) Ignore the path on the right. Carry on straight ahead. At the next junction, carry on straight ahead along the forest track: on the left, about fifty metres away, is a TMB stop, which you can use to join or leave the route. You’ll reach another fork.
(5) Carry on straight ahead. At the Fork in the road, take the path on the right which leads past a few houses and heads towards Mont Forchet: this is actually just a small hilltop occupied by a single house. Not the best spot to enjoy the view!
(6) Bypass it via a path that dips to the right. Descend the hairpin bends and you’ll come out onto the Route de Bionassay.
(7) Follow it downhill to the right and you’ll reach the junction for the circular loop.
(1) Stay on the road, negotiate the hairpin bend and walk past the chapel. All that remains is to turn left to return to the car park (S/E).