For the irregular or first time York visitor.
The Orange and Purple Halls are primarily for new equipment. Manufacturers displays are primarily in the Orange Hall.
The Red, Blue and Silver Halls are where you want to go to find postwar, MPC, and the odd old items. Some more modern and current day Lionel and MTH trans also show up.
The White Hall is the members (non commercial) hall where just about anything can be offered for sale.
The Black Hall is where you will find the modular RR display.
The small Brown Hall always seems to have newer but odd stuff.
Put on your walking shoes.