At Area51 there are several devices around the perimeter of the Nellis Range that see and hear you. At Groom Lake Road where it meets up with the border marked by "No Tresspassing" signs, there are several camera/microphone towers on the hills to the sides of the road. Farther up the road toward the highway there are ground sensors so the "camo dudes"(the security patrols) know that you are coming toward the base. The camo dudes drive around in Jeep Cherokees and will

usually park up on a hill to watch you and if you go over the border they will come and arrest you and give you a $600 fine. If you cross it again you will probably be taken into the base and interrogated.