The Hall of Armor was created by Tony Stark in his mansion in order to display the Iron Man Armours he created over the years and it was located in his workshop. This is the place where Tony stores all his Iron Man suits, either defunct or active, when or after he works on and utilizes them.

Credit for the portal and its animation goes to Fireblade28. I have no friggin' clue how to animate. Check it out:

https://www.mecabricks.com/en/models/79a8XyBwa8w