It is open to tours, now, should you wish to see it - but don't take any souveniers.
I've been to the Trinity site, and around the Nevada test site. The Sedan crater at the NTS is particularly overwhelming. If you've never seen a man-made dry hole in the ground a half-mile wide and a quarter-mile deep, well, you should.
In both cases, I had an escort, and trying to take a little something home wouldn't be worth the risk to my life, career and criminal record. I didn't spend a lot of time in the Boy Scouts, but I was there long enough to learn one adage I still like a lot: Take nothing but pictures, leave nothing but footprints. That I did.