There is a massive room inside McDonald's world headquarters filled with toys, costumes and restaurant nostalgia that the public rarely gets to see.

The company makes its headquarters in Chicago’s West Loop neighborhood with more than 2,000 employees working out of the building.

The ground floor of McDonald’s headquarters features a restaurant serving menu items from across the world, including many that aren’t available anywhere else in the U.S. Upstairs sits workspaces, test kitchens, and a training area dubbed “Hamburger University.”

Look hard enough and you will find McDonald’s official archives. The area, like the rest of the building besides the restaurant, unfortunately isn’t open to the public.

NOTE: 28 Exclusive Photos Of Amazing Retro McDonald's Items Follow Below

I did, however, get an exclusive tour during a recent press event. Archivist Mike Bullington opened his doors and let us roam around shelf after shelf of McDonald's history.

Bullington, the first ever trained archivist hired by McDonald’s, told our group that he even has an incognito eBay account to purchase rare items online to add to the collection.

Here is a look at some of the unique vintage McDonald's items that can be found in the fast food giant's official archives.

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