Every large city in the USA have nuclear waste flows under their cities silly...lol. You should plan a week on your next vacation, pick a large city and stay in the sewer system there for one week. It's a great, life changing experience. You will meet CHUD so pack weapons (CHUD=Characteristic Humanoid Underground Dwellers). They made a movie in the 1980's called CHUD that failed at the box office but later it became a cult classic and people realized the realism of the underground. The other great thing that happens after your week long tour is that your urine with glow for months! That's pretty cool.
Dont forget if you pick a city in California you have to pay an Underground Exploration Tax or UET.
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