Not sure the ADC is still out. ADC was bought by a series of companies over the decades. I loved them. I have every county of MD from I believe the Langenscheidt iteration, which my husband bought for me some 15 years ago. When I worked in hardware store in 2015 they were selling them, but yet another company and they were smaller. Not sure their status now!
I have to admit I’ve become pretty addicted to the iPhone maps. But, they don’t show the streets easily since it’s so small but the route indicates where to go.
I almost never used TripTiks but I got one in the ‘90s for my trips back and forth to home from CT. Occasionally my parents got some earlier, but mostly they just used roadmaps of the states.
When you go to ADC, it transfers you to something called ‘Kappa Map Group’.
They have a PG map, but it’s sold out.
This place might be useful:
https://www.omnimap.com/catalog/cats/maryland.htm#p5
It seems that when things get faster and easier to access, they also fall greatly in quality and become more complicated to use. ‘Progress’ is always a tradeoff.
(Have I said before that I really miss old-fashioned landline telephones?)
(sigh)