Michigan Interstate Has One of America's Lowest Speed Limits

Interstate Highways are known for their high speeds, limited access and no stopping. The design has made these roads the choice for travellers whether going long distances or across town.

In most areas these roads have speeds far greater than the surrounding surface streets: 65, 70 or 75 miles per hour are generally the norm.

👇🏼BELOW: Michigan's Interstate Quirks + These Short, Overlooked Michigan Highways Exist Only to Leave the State👇🏼

There are speed limits that are lower in urban areas where the roadway may constrict to 55 due to both increased traffic and the roadway needing to be squeezed into tighter available space.

While speeds to vary from state to state and in many situations, the Federal Highway Administration has set 70 as the interstate standard speed limit.

Speed Limits on the Mackinac Bridge Are Among the Lowest in America

Michigan has a stretch of roadway that violates this norm: Interstate 75 across the Mackinac Bridge. The passage over the Straits of Mackinac is posted at just 45 miles per hour for passenger vehicles while trucks must keep to a crawling 20 mph.

There is some debate as to the validity of the Mackinac Bridge as part of the Interstate Highway System. In addition to the lowered speed, having just a small concrete hump as a median between opposite lanes of travel is another feature of the bridge that is not interstate standard.

The YouTube Channel Beaver Geography posted a video showcasing the lowest speed limits on interstates across America. There are a few with a speed limit lower than the Mackinac Bridge's 45 mph but not many.

Other Slower Interstate Spots In Michigan?

In addition to the Mackinac Bridge, where freeways approach the international border may be slower as well. On I-75 in Sault Ste. Marie, the freeway ends at the toll plaza for the bridge to Ontario a scant 1000 feet north of the final onramp at Easterday Avenue.

Similarly at I-94 and I-69 approach the Blue Water Bridge connecting Port Huron with Sarnia, Ontario will slow as those roadway approach the toll plaza.

There's a third spot in Michigan, also along I-75, with a crawlingly low speed limit. It's in Detroit where the Fisher and Chrysler Freeways meet. I-75 mainline transitions between the two highways here using a ramp marked at 25 MPH. As it's the mainline of the interstate, it may also could towards the lowest freeway speeds anywhere in the country.

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Every Interstate Highway in Michigan Has Quirks - Here They Are

Roads are intended to get you from here to there. And very few people think about the quirks of our interstate highway system. With being as long and as varied as it is, there is bound to be an oddity or two - and in fact, you can likely find a quirk with every interstate in Michigan. We think we have.

Gallery Credit: Eric Meier