The Companions of the Cave are basically the cave dwellers. The place and time of Kahf is not mentioned in Quran and Sahih Hadith. So there is no point in looking for it. The incident is one of the types of occultation which Allah has revealed to His Prophet. However, we did not know his place and time. The Prophet (peace and blessings of Allaah be upon him) did not know all the news of the unseen. If he had known , he would not have waited for the revelation but would have told them the incident as soon as he asked the question. The cave in which the Companions stayed is also included in the Unseen. No one knows its address except Allah. If anyone specifies its place, he will be among the liars in the name of Allah.