If you are reading this, you have already seen the Disney+ series "Hawkeye" episode 5, and you may have seen any number of articles pointing out all of the "Easter eggs" - hidden hooks - to other Marvel stuff, but if you have been around for a whole, you know they are not really Easter Eggs at all.

A partially complete replica of Captain America's shield in "Iron Man" - that was an Easter Egg. Most of what are deemed Easter Eggs now are really just what we used to call "continuity." You need references to be consistent, and for that you have a continuity person who has a manual about everything that happened and where and when, what people wore, etc. Marvel wasn't always that way, things were once so loose The Hulk was Bruce Banner in one comic and Bob Banner in another, which later got ret-conned as him being named Robert Bruce Banner. In the 1970s TV show, he was neither, he was David Banner.

During episode dialogue it's mentioned Kate's address is 41st and Park. Nothing special there, except it is not a residential building. In pre-pandemic days my office address was on 42nd, across from Grand Central Station, but the building had a back entrance onto 41st, and 41st and Park on my side was one of those delicious deli buffets where you buy food by weight. Anything you want, $8.99 a pound, Bistro Marketplace.

Today it is a taco place. The other side is likewise commercial, no swanky townhouses we see in the show. 

Keep walking up 41st and you will be at the library everyone recognizes thanks to the opening of "Ghostbusters."

So what is the Easter Egg?  41st and Park is the site where the Avengers fought Loki and the first of many CGI monsters that Marvel characters fight in pretty much every movie now. Park Avenue rises at 41st into a viaduct that goes up and around Grand Central, it is a fun ride if you are in a car, and that Park Avenue viaduct is where Loki got sent back to Asgard. They didn't put up townhouses on the site where The Avengers saved the world so the address is just an Easter Egg. Unlike the "Sex And The City" building, they don't want actual residents sitting on the steps to take photos so they created an Easter Egg where the only thing you'll get is a Starbucks.

If you played "The Division" that viaduct was also a prominent mission as well, and I did a NYC walkthrough of that game also.

No, despite what you see in "The Avengers" or "The Division" (top part of the image) or "I Am Legend" you can't walk on it, I took the below picture of the real one in an Uber.