The Hera Cave on Mount Al-Nour is where the Prophet Muhammad SAW first received verses of the Quran through Archangel Gabriel. Though the Hera Cave is not part of the Haj routine, many Muslims still rush over to the cave just to get a glimpse of what the Prophet went through when the Quran was revealed to him.
It is said that it takes about 20-30 minutes for a really fit person to climb to the cave. For others, it might take as long as 2 to 4 hours. For someone, who has come from really far for Haj, it is surely worth every minute to climb up to the Hera Cave.
Since the cave is very small, it is not encouraged to spend a lot of time there. This has been said by Arabic officials as they think offering prayers or reading the Quran there or in there will not provide enough time for other hundreds of muslims who are eagerly awaiting their chance to go inside.