Are opium dens legal in the US?

Opium dens are not legal in the United States. The use, possession, and distribution of opium and its derivatives are prohibited under federal law, primarily due to the Controlled Substances Act. While historical opium dens existed in the 19th and early 20th centuries, such establishments are now considered illegal and associated with drug trafficking and abuse. Law enforcement actively works to combat any resurgence of such activities.