I used to be in the real estate business, you'd be surprised at the number of houses built from the mid-50's through about 1970 that had bomb shelters. People convert them into guest rooms, wine cellars, small recording studios, you name it. Give it a try, it will be dead quiet from external noise.
The best story I know about a bomb shelter happened about 1969. There was a wealthy couple who lived near me as a kid. They had dedicated bomb shelter on the property, and even better, a large swimming pool. When they left for their month long summer vacations, everyone and their brother was in that pool until they came back. We'd all been curious about what was inside that bomb shelter since it had been installed in the early 60's. One day, curiosity got the best of couple of the older guys and they came prepared with a tire iron and a crowbar determined to get in. They did, and they were stunned by what they saw, the couple had converted it to an S&M dungeon.
Literally everyone in the neighborhood was over there inside of a half hour to check it out. It was a scandal and a half, not just because of the contents, everyone knew they were odd, but because the were both educators, he was the principal at nearby HS, she was a teacher at the local grade school. The cops came up looking for someone to arrest for breaking and entering when they got the call, but they were as stunned as everyone else by the sight, and forgot about it. Besides, the two guys who had done the deed had ditched their tools and were milling around the crowd playing innocent, while all the guys who'd witnessed the opening weren't saying crap, it was against our code to tell on anyone who wasn't danger to the public.
The couple was back the next day, the thing boarded up, and the house was on the market inside of a week. They moved away never to be seen again. The guy who bought the place razed the bomb shelter as he didn't want people coming around gawking. He was a good guy, and had a cool son about our age who fit in. Due to him we had the run of the place for swimming and ball games for years.