After spending nearly all of our 40-some years in the Northeast, my wife and I had never experienced a truly dark sky. The best we'd been able to see, on the clearest, coldest winter nights, was still almost-black with a smattering of stars. We could sometimes discern the Milky Way, but it was mostly a case of "Oh, that must be it, maybe?" Not nearly as clear and distinct as the photos we'd seen.
On our first trip to Grand Canyon (pre-RV days) we checked into our hotel in Tusayan, had a nice dinner, then drove to the South Rim after dark. Approached the rim I could tell that this was going to be a unique experience for both of us. As we entered the parking lot of an overlook I had her close her eyes until told she could open them. I parked the car, then helped her out (eyes still closed), walked her to the rail at the rim, positioned her face looking almost straight up and out over the canyon, then told her to open her eyes.
The canyon was pure, empty blackness, the cosmos a carpet of tiny lights above us, the silence was deafening. The sudden, strange juxaposition of empty blackness BELOW and soft white light ABOVE literally took her breath and her balance away. We're both glad I was holding on to her.
I highly recommend this for first-time visitors.