I wish I had known this in the 1970s.
I lived in Hartford, Connecticut and would spend long weekends in New York City.
I would have visited and dined in a few of these.

bump off a few mobsters to get on the reservations list!

I'm glad I came of age when I did (1990s), but one other period of time and place I wish I could have experienced would be 1970s New York City. It just seemed so gritty and dirty and exciting. I don't know what makes me wish I could have experienced that. Photos from that era fascinate me.

Interesting for sure. And I was too ignorant to grasp the nitty gritty part of some of it.

I'd walk all over the Times Square area day and night (my hotel was nearby), taking in the sights.
Looking & thinking back,
many of those who loitered there were male and female hustlers/prostitutes.

Unlike today there were many porn shops, X-rated movies theaters, etc.

At the time I had a book "NYC On $45 A Day".
My hotel, old but decent, was $17 a night.

This was between 1969 - 1975.

No. 2, Sparks Steak House

In the early '90s, I was invited to a business dinner at Sparks along with about a dozen others. We had a nice big table. The drinks were generous, the food delicious and copious and the service was excellent. I knew I had heard of the restaurant but at the time just thought it was another midtown steakhouse. When I got home, my wife reminded me that was where Castellano had been gunned down. Regardless, we had a good dinner but I've never had the occasion to return.

No. 8 Umberto's Clam House

NYC's Little Italy has been shrinking year-by-year over the past 25 years or so and many excellent restaurants are gone. My favorite was a high-end place called SPQR where I once got stuck with a dinner bill for 12 people = $3,500! Thankfully, my expense account covered it. Still, it was an amazing dinner.

Umberto's has claimed one of the top spots in Little Italy and although it's also pricey, (entrees are high-$20s to low-$30s), the quality is exceptional. They obviously specialize in seafood which is fresh, delicious and beautifully presented. The wait staff is superior and it's fun to glance around at the other patrons, (don't stare unless you're really brave and definitely no photos!).

New York City doesn't have the kind of macabre history of some European cities but these infamous joints have their own stories to tell. Maybe it would be fun to visit each of these eateries although the social clubs might be difficult to get into.