I remember them in Washington DC in 1986. I was stationed at Bolling AFB, just got married (in May) and moved to an apartment near Camp Springs, Maryland, just south of DC.
Me and my bride would walk our dogs in the nearby woods and fields. The cicadas sounded like a pulsating alien spaceship landing. It was eerie!
I know Camp Springs well - I went to high school there in the early ‘70s.