Crossing the Mackinac Bridge in an RV

Spanning the two Michigan peninsulas is the Mackinac Bridge, the longest suspension bridge in the western hemisphere . It is always a highlight of our trips to the Upper Peninsula. When you say “Big Mac” to a Michigander, the bridge is what they think of, not the hamburger.

Counting the approaches, the bridge is five miles long.

What makes it so interesting is the very nature of its construction. A suspension bridge is designed to move to accommodate wind.

And high above the Straits of Mackinac, where Lake Michigan merges with Lake Huron at the very tip of the Michigan mitt, there is always wind.

mackbridge

The view from Mackinaw City of the Mackinac Bridge. And yes, the two names are spelled differently. Pronounced exactly the same but spelled differently. I have no idea why.

In fact, according to the Mackinac Bridge Authority, the state agency that runs the bridge, it is possible that the deck at center span could move as much as 35 feet (east or west) due to high winds.

Seriously.

This would only happen under severe wind conditions, mind you. And the deck would not swing or “sway” but rather move slowly in one direction based on the force and direction of the wind. After the wind subsides, the weight of the vehicles crossing would slowly move it back into center position.

Sometimes, the bridge is shut down. Electronic signs along I-75 so alert drivers and a low power radio station continuously broadcasts bridge conditions. Large trucks usually require an escort.

But RVs usually have no problems.

I say usually. I’ve crossed the bridge in our Roadtrek a dozen times. On a couple of occasions, I was aware of some pretty stiff cross winds. Nothing that caused any serious apprehension, but enough to keep my speed down.

Occasionally, there have been vehicles rolled over on the bridge because of high winds.

In 1989 a woman driving a two-year-old Yugo inexplicably stopped her super light weight vehicle on the bridge over the open steel grating on the bridge's span. A gust of wind through the grating blew her vehicle off the bridge.

That's the only death not attributed to accidents or suicides. The most recent suicide was late last year, by someone who jumped over the rail. In 1997  a man in a Ford Bronco intentionally drove off.

But such incidents are very rare.

Yet, because of the nature of suspension bridges, there's always an element of adventure in crossing the Big Mac.

The view is always spectacular.

I put together this little video during our most recent crossing. It was late on a cloudy day on mid-September.

Some 200 feet below it, ferry boats could be seen making their way back and forth to nearby Mackinac Island from Mackinaw City, the last town in the Lower Peninsula and St. Ignace, the first town in the UP.

Before the bridge was opened in 1957, automobile ferries made the crossing.

Every Labor Day, people can walk across the bridge. I've participated in a couple of bicycle rides that also cross the bridge as well. But the bridge is only open for vehicular traffic except on a very few special occasions during the year.

So driving is how most of us cross. If you haven't driven across the Big Mac bridge, put it on your bucket list.

If you want to spend the night and check out the bridge, the best place to do so is on the UP side, at Straits State Park in St. Ignace. There are spots right along the lake shore with a view like this:

mbstignac

From Straits State Park in St. Ignace, looking south. This was from our campsite there.

If you just want to get close and take some photos or maybe have a picnic, the Fort Michilimackinac State Park on the Mackinaw City side has lots of  RV parking with great bridge views like these:

mbsunset

Sunset, looking west from Fort Michilimackinac State Park in Mackinaw City

mbsunseet2

You can walk right under the bridge at Fort Michilimackinac State Park in Mackinaw City

mbsunset3

Counting the approaches, the Mackinac Bridge is five miles long. This is from Fort Michilimackinac State Park in Mackinaw City

 

Meanwhile, here’s some facts and figures on the bridge:

Total Length of Bridge (5 Miles) 26,372 Ft. 8,038 Meters
Total Length of Steel Superstructure 19,243 Ft. 5,865 Meters
Length of Suspension Bridge (including Anchorages) 8,614 Ft. 2,626 Meters
Total Length of North Approach 7,129 Ft. 2,173 Meters
Length of Main Span (between Main Towers) 3,800 Ft. 1,158 Meters

 

HEIGHTS AND DEPTHS

Height of Main Towers above Water 552 Ft 168.25 Meters
Maximum Depth to Rock at Midspan Unknown Unknown
Maximum Depth of Water at Midspan 295 Ft. 90 Meters
Maximum Depth of Tower Piers below Water 210 Ft. 64 Meters
Height of Roadway above Water at Midspan 199 Ft. 61 Meters
Underclearance at Midspan for Ships 155 Ft. 47 Meters
Maximum Depth of Water at Piers 142 Ft. 43 Meters
Maximum Depth of Piers Sunk through Overburden 105 Ft. 32 Meters

 

 

CABLES

Total Length of Wire in Main Cables 42,000 Miles 67,592 km
Maximum Tension in Each Cable 16,000 Tons 14,515,995 kg
Number of Wires in Each Cable 12,580
Weight of Cables 11,840 Tons 10,741,067 kg
Diameter of Main Cables 24 1/2 Inches 62.23 cm
Diameter of Each Wire 0.196 Inches .498 cm

 




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  • Laura H P

    Ah…love that bridge!

  • Dave Bates

    I’ve crossed Big Mac four times in a Class A motorhome towing a Dodge minivan and have never had a problem. It is a unique experience and the scenery in the UP is well worth the trip.

  • Linda

    We have crossed the bridge many times in all sorts of weather, beautiful sunny days and during raging snowstorms! Prefer the sunny calm days as crossing in inclement weather can be a heart stopping adventure!

  • Bill

    Nice article Mike. We crossed Big Mac last month in a Roadtrek RS and enjoyed the view as we toured UP for the first time. We also spent the night at Straights in St. Ignace with the same view of the bridge from our camp site, before heading over to the Mac Island the next day.

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  • Sue

    We live in the UP and have crossed the Mighty Mac thousands of times over the last 40 years. Only one time did I get sick from being blown around in a van.. many many years ago.. it is an awesome bridge and one everyone should cross.

    [email protected] has shared a video with you on YouTube

    The Five Mile Dream (1958)
    by USAutoIndustry
    Building of the Mackinac Bridge, Michigan

    this is a great video of when they made the bridge. Those were very brave men.

  • A lot of good memories going back and forth on that bridge.

  • Been there dome that years ago. It was raining and under consrtruction.

  • Been there and done that.

  • Love the Big Mack! Funny, sometimes when we cross with the RT we get charged the rate of a regular van. Sometimes we get charged double. Who knows why?

  • We did this in September, beautiful bridge.

  • We have done that!

  • Crossed the Big Mac this summer with Lori Berlin Russell. Stay off the metal grate…I felt much more comfortable on the asphalt.

  • Crossing g the Mac in 13 ft semi under high wind advisory you definitely feel the wind if you are empty it really obvious Karla Cavender Tuggle done it many times

  • More fun than crossing on the bridge was crossing on the ferry to mackinac island.

  • Been there and done that……

  • Many. Times only one under escort. Finally have gotten ho hum about it. Biggest thrill. Is crossing it on an antique tractor with 1000 other tractors in September every. Year. Whole families do.it. crossing in a doodle bug is on my bucketist

  • Crossing it in a car is bad enough.

  • I do not do high bridges like that one well.

  • Been there done that before there was a bridge, watched them build it

  • Crossed it several times this year……I drove across coming home….luckily no wind but I hate being above the railing. I’ve walked across and driven a car across but our RV…didn’t enjoy driving it.

  • I’ve been on this bridge!!!! Wow a real ruse

  • We did Mackinac Island. Awesome.

  • Darlene Achee

  • No way!

  • Looks awesome…would love to see it!!

  • Did that this summer too.

  • Did that in a truck and 5th wheel while they were working on the bridge 2 years ago. Kind of scary then.

  • Been there, Done that.

  • Our family crossed it in a VW. Scary EEEEEEEEEEE

  • Been there done that. Loved it.

  • James Murray Plunkett

  • Wow I would love to cross this bridge, in our motor home!! Maybe next year!!

  • Crossed it many times and did the Labor Day Bridge Walk also ! BEAUTIFUL piece of engineering!!! You ought to see it from the deck of a lake freighter sometime !!!

  • Really a wonderful bridge!!!!!,!!!

  • Early fall 2006, spent two weeks in the area. Ferry to & bicycling Mackinac Island; hikes to some of the old Maple syrup farms; Whitefish State Park; camping on the beach of Lake Huron with a view of the bridge – every day was awesome!

  • Done it – white knuckle and hiding under a blanket (hubby was driving). I would rather walk, or swim, thank you. Bridges occasionally fall down, you know. And it isn’t so very far out of the way to drive around the lake instead of taking bridge.

  • Michelle Kruger Cervene

  • We did it in a “new” volkeswagon squareback!

  • We have not done it yet in the motor home hate bridges that high up have been on it in van and pickup truck scares me to death

  • I’ve crossed it with a horsetrailer towed behind following two big motor homes. They closed the bridge behind me and the two motor homes in front of me lost their canopies as we crossed with nothing but fringe left. It’s not a bridge for the meek especially in a storm.

  • Did that last spring. It was great!

  • We did it on a motorcycle!

  • Last time we crossed the bridge-truck and 36′ 5th wheel-we were the last to cross before they closed it due to the wind! Zowie!

  • Mackinac bridge is scary! Glad I wasn’t driving! We loved Mackinac Island. ♥♥♥nn

  • Fortunate enough to live and work at the Mission Point Lighthouse 2 times. What an experience!!

  • We did that last month. Now I cam say I have traveled the entire length of I 75. From Michigan to the Florida Keys

  • Nice angle on the pic.