What it takes to get into Michigan's private city where all the gas is free and cars don't have license plates
Published on Feb 04, 2026 at 4:07 PM (UTC+4)
by Ben Thompson
Last updated on Feb 04, 2026 at 9:18 PM (UTC+4)
Edited by
Mason Jones
Inside Michigan’s private city, the gas is free and cars don’t have license plates – but here’s what it takes to get in there.
This is Milford Proving Ground, owned by General Motors, and sitting between the main GM hubs of Flint, Detroit, Lansing, and Pontiac.
It was purchased by GM back in 1923, costing just north of $100,000.
Many people don’t get to see the inside of Milford, but how can you gain access to it?
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What happens at Michigan’s private city?
On this 4,000 acres of land, there’s 174 buildings and 147 miles of test roads.
Several test tracks dominate the landscape, ranging from dirt roads to hills to bumpy concrete with purpose-made potholes.
Given that the land is used for testing cars, the gas is free at the on-site gas station.
And with it being on private land, no license plates are required.
It does sound like a fun place to drive, but can just anyone go in there?
Who has access to Milford Proving Ground?
The facility is strictly restricted to GM employees.
And even in that regard, there’s different levels.
Out of the thousands of GM employees around the world, only a select few get to drive the roads of Michigan’s private city.
There are six levels of driving privileges, with employees on Level 1 only able to access the roads between buildings.
At Levels 4, 5, and 6, employees can do high-speed drives. Of 81,000 salaried employees at GM, only 200 are at these upper echelons, Detroit Free Press reported.
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There’s a lot of secrecy in the world of cars
We tend to think of cars as being a very public aspect of our day-to-day lives – we see them everyday, after all.
But there’s plenty about the automotive world that is shrouded in mystery and exclusivity.
Over in the UK, there’s this supercar event which is strictly invite-only.
Out in the middle of Death Valley, one secret road was waiting to be discovered when a Californian YouTuber stumbled across it.
And there’s no forgetting the cars left on farms which go undiscovered for years.
Ben joined Supercar Blondie in February 2025 after being published by international organizations including LADbible, The Sun, the New York Post, and the Daily Mail. He covers supercars, rare and collectible vehicles, aviation, luxury assets, and the fascinating people behind them. His reporting has explored everything from seven-figure supercars and historic Ferrari collections to unusual aircraft adventures and extraordinary automotive discoveries from around the world. Ben has also gained first-hand insight into vehicle craftsmanship and customization, including visiting specialist workshops to see bespoke vehicles up close.
