Totally worth the visit. It was a rainy day in Vegas (I swear) so this was the perfect time kill. Great stories about the importance (with a little controversy thrown in) of above/below ground testing that took place NW of Vegas. Most Importantly- this is the only org that can get you - once a month - onto the actual grounds of the tests. Call them for details as dates are inconsistent at best and try to do so months in advance tho supposedly you might get lucky with an unclaimed seat. We didn't know about the visits till a docent told us about it. The Groupon others mentioned was available but since this is affiliated with the cash-strapped Smithsonian, we just paid full price. ONLY downside was a poorly stocked gift shop.