Park at the Porte de Provence (small car park after the bridge on the right coming from Sisteron). On this route, always follow the yellow markings.
(S/E) Reach the start of the climbing routes, which you will follow on your right, along a fence that follows the curves of the walls, to begin the hike in the undergrowth, which is very pleasant when the weather is nice. Gradually gain altitude, discovering a beautiful view of Sisteron and its citadel.
(1) Turn left. Cross beautiful stretches of grass in September/October.
(2) Beautiful view of the citadel. The path continues gently with little elevation gain.
(3) Take a steeper path on the left that leads you towards the walls of La Baume. This section has little shade and can be a little difficult in direct sunlight.
(4) Enjoy the cooler air and continue on the left. The slope becomes steeper again as you approach the walls, sometimes requiring you to get down on all fours.
(5) You will finally arrive at the wall. Two holes are visible: these are small caves, but they are not the ones you are looking for! You will need to continue to the right until you reach a ladder and a handrail that allow you to climb up to the first cave. It is relatively bright. You will come out onto a small balcony with a beautiful view.
However, continue on your way to the second cave, but not before noticing an inscription on a stone on the ground. The second cave is much darker. A torch is essential for finding your way around. You may have to leave your rucksack behind, as I did, in order to get through on all fours and then get out again.
You will arrive at a beautiful open space, again like a balcony, and continue on your way, noticing another inscription, this time vertical.
(6) A little further on, use another handrail, which then becomes more vertical, but is still well equipped with a handrail. When you reach the top, walk along the ridge to the right until you reach a panoramic view.
(7) Retrace your steps and, at the top of the last handrail, continue west. The path then turns right and heads northwest. The rest of the hike is easy.
(8) You will arrive at a road, which is not very pleasant, and follow it to the left before taking a fairly wide path on the left, in a hairpin bend to the right of the road. This path will then narrow as it turns west to join Sisteron. Descend, following the yellow markings, to the car park below (S/E).
Otherwise, the panoramic views are magnificent. Sisteron, its village and its beautiful citadel are revealed in all their splendour. At the top, you can see griffon vultures circling above your head, well aware of your presence. What magnificent birds! The end of the hike is less interesting. You descend through a forest and finish on a forest path that is half in the sun and half in the shade.