Despite its reputation as the most secretive element of the intelligence community, the National Security Agency (NSA) is the only US agency to have a museum open to the public, the National Cryptologic Museum (NCM). Even if admission were not free, a visit would still be well worth the effort. The museum is located opposite the agency's headquarters at Fort Meade in Maryland, around 40km north of Washington DC, and is not accessible by public transport. 

This isolation limits the flow of curious