Well, on either side of the Combe Vallier with the Le Ruhaut stream, normal bicycles cannot get through. Or you are fit enough to shoulder the part. There is a lot of altitude to master over stairs and slippery paths. To top it off, the ladder beckons. So of course it's doable for absolute freaks with the appropriate equipment, or as a hiker it's not a challenge. Everyone else who doesn't get anything out of such escapades or the bike is too heavy or you don't have the necessary constitution to overcome such obstacles leave it it better!
However, the corner is worth a visit. Imposing landscape and the creek has left a deep ditch. Pretty rock formations tower up on both sides.