There is a private city in Michigan where all the gas is free and the cars don't have license plates
Published on Nov 29, 2025 at 12:15 AM (UTC+4)
by Henry Kelsall
Last updated on Nov 27, 2025 at 1:44 PM (UTC+4)
Edited by
Emma Matthews
America has a secret and private city in Michigan owned by General Motors where all the gas is free, and none of the cars have license plates.
This isn’t a traditional city, however, but a proving ground for General Motors that allows them to test out all of their cars in a wide array of situations and scenarios.
Nearly 5,000 employees are working in this unusual place, and yes, all of the gas is actually free.
Not many people get to see inside this city, which adds to the mystery and coolness of the location.
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What is the name of the private city?
The location is the Milford Proving Ground, located in the heart of Michigan.
It has been a central vehicle testing location for over 100 years, and one that various GM brands have tested at.
Milford sits neatly between the main GM hubs of Flint, Detroit, Lansing, and Pontiac.
The city was bought by GM back in 1923, at the time costing just over $100,000.
It was called ‘The Bluffs’ thanks to the rugged terrain and 267ft of elevation change.
In 2025, the site now covers over 4,000 acres and has more than 150 buildings.
There are also 150 miles of two-lane roads, 131 miles of pavement, and 16 miles of gravel.
In fact, if it were one continuous highway, drivers would take two hours to cover it.
Gas is free at the Milford Proving Grounds
One factor behind Milford’s creation was to prevent the public from seeing prototypes being tested.
But the site also has a few other interesting details.
With so much testing taking place at Milford, a lot of gas is required.
Thankfully, for those refueling at the site, the gas is completely free from its very own gas station.
Another unique feature is that no car here has a license plate.
As it is all private land and with many cars still in development, license plates just aren’t needed.
An off-road section also means SUVs and off-roaders can be tested at Milford.
Sprinklers are used to simulate rain and test the grip levels of the cars in wet conditions.
To put it simply, Milford is an amazing location and one of America’s best automotive test facilities.
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Henry is a content writer with nearly ten years experience, having written for various publications since 2017. Qualifying with a Sports Journalism degree from Staffordshire University, Henry loves all things automotive but has a particular soft spot for classic Japanese cars and anything Lancia. He also has a curious passion for steam locomotives.
