"True" New Yorkers seem to have memorized which numbers are between which numbered Avenues --- at least my son has done this since moving there first for college, then a job.
This is one of those 90/10 rule things where just learning a post-it note worth of trivia covers you for over 90% of instances. I'm sure he's competent at navigating especially in the ordinary places reachable by ordinary subway ride. The corner that flummoxes me is that inexplicable void in the map. The big empty part of the subway system sandwiched between the EFMR and JMZ lines. That curious combination of Newton Creek, Highland park, an archipelago of like a dozen large cemeteries, more than a few heavy industrial zones, and freight rail tracks. I've seen parts of the map in this no mans land where numbered Ave's just straight up skip over a half dozen other numbers which I know exist elsewhere on the map. However the grid was zippered together, there is a seam in it and this is it.
There is actually an official algorithm for estimating the cross streets given any address within the Manhattan grid. I don't know if it still is, but it used to be published in fine print on bus system maps. It's a little too complicated to memorize, but you could easily keep it on a note card in your wallet and do the calculations in your head or with your phone calculator.
Right. Manhattan grid. That's easy. I'm talking about the grid in Queens. In particular the middle of Queens. It becomes extremely non-grid conforming in a way a calculator rule can't fix.
I can do this in Amsterdam as well, but there it is a lot more complicated, especially on the canals. But I usually can aim for the right block just knowing the house number, and even/odd says which side of the street or canal to be on.
