27 votes

Mackinac Bridge


Mackinac Bridge

Snow and the Mackinac Bridge Mackinaw City, Michigan Michigan Sea Grant Extension, Carole Y. Swinehart

Enviromental Protection Agency

View this photo at epa.gov

BH Photo #315043

Street View 


The bridge won the award of merit from the American Institute of Steel Construction (AISC) as the "Most Beautiful Steel Bridge" in Class I in 1958. Designated in 2010 as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers (ASCE).


Suspension bridge over the Straits of Mackinac on I-75 at Mackinaw City
Emmet County, Michigan, and Mackinac County, Michigan
Open to traffic
Opened Nov. 1, 1957
- American Bridge Co. of New York
- David B. Steinman of New York, New York (Design engineer)
- Merritt-Chapman & Scott Corporation of New York, New York (Foundations)
Wire suspension main span, with an assortment of deck truss designs and a piled rock causeway for approaches.
Length of largest span: 3,800.0 ft. (0.7 mi.)
Total length: 19,248.6 ft. (3.6 mi.)
Deck width: 47.9 ft.
Also called
Mighty Mac
Approximate latitude, longitude
+45.81917, -84.72750   (decimal degrees)
45°49'09" N, 84°43'39" W   (degrees°minutes'seconds")
Approximate UTM coordinates
16/676536/5076467 (zone/easting/northing)
Quadrangle map:
Saint Ignace
Average daily traffic (as of 2007)
Inventory numbers
MINBI 24186000000B010 (Michigan bridge number on the National Bridge Inventory 2010 and before)
MINEW 02456 (Michigan bridge number on the National Bridge Inventory 2011 and later)
BH 20027 (Bridgehunter.com ID)
Inspection report (as of July 2018)
Overall condition: Fair
Superstructure condition rating: Very Good (8 out of 9)
Substructure condition rating: Very Good (8 out of 9)
Deck condition rating: Satisfactory (6 out of 9)
Sufficiency rating: 56 (out of 100)
View more at BridgeReports.com

Update Log 

  • June 22, 2022: New photos from John Bernhisel
  • May 22, 2021: New photos from Josh Schmid
  • May 21, 2021: New photos from Geoff Hubbs
  • February 5, 2021: New photos from GS
  • April 17, 2018: New photo from Royce and Bobette Haley
  • April 15, 2018: New photos from Richard Doody
  • October 23, 2017: New Street View added by Matthew
  • September 24, 2017: New photos from James Baughn
  • September 15, 2016: New Street View added by Dana and Kay Klein
  • July 10, 2016: New photos from Royce and Bobette Haley
  • February 4, 2015: Photo imported by Dave King
  • October 18, 2014: New photos from Patrick S. O'Donnell
  • August 15, 2013: New photos from Michael Miller
  • May 30, 2013: New photos from M. D. Caillet
  • July 13, 2012: Updated by Luke Harden: Corrected builder
  • September 3, 2011: Updated by C Hanchey: Bridge is not listed on NRHP
  • December 16, 2010: New Street View added by Nick Brnot
  • November 27, 2010: Updated by Nick Brnot: fixed spelling of "counties" in History
  • October 30, 2010: New photos from Nick Brnot
  • October 16, 2010: New photo from Nick Brnot
  • October 8, 2010: Updated by Nick Brnot: Added some history
  • September 1, 2010: New photo from Nick Brnot
  • August 19, 2010: Updated by Nick Brnot: Added Approach Detail
  • March 17, 2010: Updated by J.R. Manning: Added Street View
  • November 17, 2009: New photo from Robert Thompson
  • September 8, 2009: New photos from Bob Morgan
  • August 16, 2008: New photos from J.R. Manning


  • HAER MI-329 - Mackinac Straights Suspension Bridge
  • J.R. Manning - thekitchenguy [at] sbcglobal [dot] net
  • Robert Thompson
  • Bob Morgan - morgans212 [at] att [dot] net
  • Wikipedia
  • Todd Walker
  • C Hanchey - cmh2315fl [at] yahoo [dot] com
  • Luke
  • Historicbridges.org - by Nathan Holth
  • Michael Miller - michael_a_miller [at] yahoo [dot] com
  • Patrick S. O'Donnell - 1 [dot] 991km [at] comcast [dot] net
  • Royce and Bobette Haley - roycehaley111 [at] yahoo [dot] com
  • Dana and Kay Klein
  • HAER MI-329 - Mackinac Straights Suspension Bridge, Spanning Straight of Mackinac, Mackinaw City, Cheboygan County, MI
  • Richard Doody
  • Geoff Hubbs
  • Josh Schmid
  • John Bernhisel - Johnmbernhisel [at] gmail [dot] com


Mackinac Bridge
Posted October 3, 2012, by Todd D. Walker (waycool67 [at] rocketmail [dot] com)

I offer admiration to all who are or were involved with the upkeep of the Mighty Mac. I asked my girlfriend to marry me right next to the bridge on Sept 21st. Can't wait for the new orthotropic deck planned for it soon. Worth the $4 toll. AWESOME bridge!

Mackinac Bridge
Posted October 2, 2012, by David Rees (dave32 [at] AOL [dot] com)

Main Span length 3800 feet. I was engineer for cable construction, 1956.

Mackinac Bridge
Posted April 3, 2012, by Todd D. Walker (mrwalk11 [at] hotmail [dot] com)

I cannot believe that these pictures are 40 years old. I started my fascination of bridges at four years old. Yes, that tyke is me.

Mackinac Bridge
Posted April 3, 2012, by Todd D. Walker (mrwalk11 [at] hotmail [dot] com)

I restarted a tradtion I begun in the 90's, walking Big Mac. What a greater time for pictures.

Mackinac Bridge
Posted September 12, 2011, by Tony Dillon (spansaver [at] hotmail [dot] com)

I'm ready to see the "Big Mac" again, but am waiting patiently until the Fort Street Bridge in Sault Ste. Marie is resurrected to make the trip.

Mackinac Bridge
Posted September 12, 2011, by Todd D. Walker (mrwalk11 [at] hotmail [dot] com)

I had a wonderful five mile hike a week ago. Yes, it was cloudy Labor Day on the bridge. After lunch at DQ in Mackinaw City I got some great pics and the Mighty Mac looked great.

Mackinac Bridge
Posted July 4, 2011, by Nathan Holth (form3 [at] historicbridges [dot] org)

The Ambassador bridge is not to be "twinned" but instead has been planned for complete replacement by a different structure type, a cable-stayed bridge. Current plans have called for leaving the historic bridge standing, albeit completely unused, next to its replacement. The approach spans have already been built, but the owner's failure to file proper papers halted construction. Further, plans to built another crossing that would instead be publicly owned, may ultimately change the owner's mind on what to do here.

At this time, there are no current plans whatsoever in the immediate future to twin or replace the Mackinac Bridge.

Mackinac Bridge
Posted June 27, 2011, by Todd (mrwalk11 [at] hothail [dot] com)

Yes, it is the Ambassador Bridge concidered for a twin. I googled "Mackinac Bridge" "news" and learned the Mighty Mac is not concidered for a twin. I feel good on that one.

Mackinac Bridge
Posted June 27, 2011, by Tony Dillon (spansaver [at] hotmail [dot] com)

Todd, I think the gentleman may have gotten confused with a possible plan for the Ambassador Bridge that links Detroit with Canada.

I looked around the web and found this article that talks about the possibility of this and does also mention the Big Mac Bridge, but just in reference:


The Ambassador Bridge is about 30 years older than the Mac, and apparently carries a large amount of commercial traffic between the 2 countries.


Mackinac Bridge
Posted April 9, 2010, by Todd D. Walker (mrwalk08 [at] aol [dot] com)

The Mackinac Bridge is my inspiration point having been fascinated by it for forty years come September 2011. I plan on heading up to see it and a lighthouse that sits in its awesome shadow in a few months hopefully. Always nice to see others sharing simular feelings as I and posting their thoughts on this forum.

Webmaster's note: The photo that was here has been incorporated into the main site.

Mackinac Bridge
Posted April 9, 2010, by Ray Chapin (r-chapin [at] sbcglobal [dot] net)

Big Mac is mind-boggling as well as beautiful! I grew up about 35 miles south of the bridge and remember watching the construction progress of the bridge. I crossed the bridge on the first day it was opened to traffic, and have walked it with my son several times on the annual Labor Day open walk. It still fascinates me to see it. One of my high school classmate's wife's father performed the indian ceremonial blessing dance on top of one of the main towers when its construction was completed (I think it was the north tower).

Anyway, it is always a joy to see it.

Mackinac Bridge
Posted March 18, 2010, by Anthony Dillon (spansaver [at] hotmail [dot] com)

What's not to like about the Big Mac!

Mackinac Bridge
Posted March 18, 2010, by Todd D. Walker (mrwalk08 [at] aol [dot] com)

I am happy that there are plenty of people that have the same admirations for the Mackinac Bridge as I do

Mackinac Bridge
Posted October 10, 2009, by mary wolski bennett (mbennett4408 [at] gmail [dot] com)

I grew up in this area, all of my family still lives there. Grwoing up in the area you never thought of how magnificent this bridge is. I really appreciate it now that I live in ohio. Thanks for all the pics and comments.

Mackinac Bridge
Posted September 5, 2009, by Todd, aka. "bridgebuilder" (mrwalk08 [at] aol [dot] com)

These pics were taken Aug 18th by my girlfriend, Michelle. This group of pics is the first of her's I am posting. I had the feeling "I wish I was there". Shelly took the opportunity of Mackinac for a family trip with her kids. Another noteworthy idea is to check out the numerous lighthouses scattered about the Mackinac area. As I love bridges, she enjoys lighthouses.

Mr Baughn, why don't you concider adding a "lighthouse" themed site, or add them as a "link". Meeting Shelly gave me a new interest besides bridges, "lighthouse".

Webmaster's note: The photos that were here have been incorporated into the main site.

Mackinac Bridge
Posted August 16, 2008, by Todd (groovyheart67 [at] yahoo [dot] com)

I see my soul and gain inner strength when I look at the Mighty MAC.

Mackinac Bridge
Posted July 5, 2008, by Todd (hippiewalk [at] yahoo [dot] com)

I hope more people post pictures of my "inspriration point" on this website. I been fascinated with the Mackinac Bridge since 1971 when I was 3 yrs old. It is a well maintained toll bridge that is lovingly cared for. It is the "crown jewel" of the Great Lakes area. It is not "functionally obsolete" in my eyes. It is a beautiful bridge, and should be an icon like the Golden Gate in California!

Mackinac Bridge
Posted June 16, 2008, by David Yates (david_y [at] bellsouth [dot] net)

A very impressive bridge as the first picture shows from several miles away. Second picture shows the bridge from the north shore