A road safety barrier having a plurality of ropes supported by posts rigidly mounted on or in the ground is described. Each rope is held in tension against the posts and supported in a longitudinally oriented indentation in a side of the posts. The ropes are released from a post and the post is not pulled from the ground when a vertical force is exerted on the rope. The post may have a circular cross-section and the indentation has a bottom oriented substantially parallel to the ground such that the rope is biased to exit upward out of the indentation. The ropes when weaved are tensioned against the posts and this gives rise to a combined frictional resistance to displacement of the ropes relative to each post along the length of the safety barrier.