If you have been to the island and only ate fudge, you are missing out!! Don't be put off by the thousands of bikes on the island, because I rode 10-12 miles of the "fun trails" without coming across another biker on a busy summer weekend.
There seems to be a pretty amazing amount of trails (single track, two tracks, and paved bicycle only trails) throughout the center of the island. Some is easy, some is very difficult. The Tranquil Bluff Trail is my favorite and varies from easy on the north end to some pretty wild stuff back at the south closer to town (that trail turns into the Manitou Trail between Arch Rock and Robinson's Folly). A lot of those trail are right along a ridge (seems like it's several hundred feet high) overlooking Lake Huron and the main paved trail that surrounds the island. There are quite a few spots that you would certainly not want to fall off (or you could easy not ever be able to ride, or breath, again if you know what I mean).
Oh yah, bring your own bike to the island if you want to ride the fun trails as all the rentals are for touring around the island on the flat paved trails (and I probably wouldn't trust them to even do that). Most of the ferries charge an additional $8 (round trip) for a taking your bike to the island and back.
Watch out for road apples!!
 | Arch Rock Bicycle Trail |  | 0.6 mi |
I like Mackinac Island, and I like the paved trails, but there are no true Mountain Bike trails on the island. I tried "Tranquil Bluff Trail" from Arch Rock, but it was not very tranquil. I snapped my rear derailleur hanger, bent my chain, and scootered my bike to the bike shop and then they didn't have the part I needed.
In a nutshell, you will be jumping off your saddle for many intense, rutty climbs. That goes to say that you will be bombing down short, gnarly downhills. Plan on enjoying the island from the main trails and avoid the hassle and vacation interruption I had.
| ThankLots of trails, both marked and unmarked. Be aware that "Tranquil Trail" is not a tranquil bike ride. It was fun but there arebmany steep hills up and down with MANY roots. Erosion has definitely taken its toll on the trail. Nevertheless, some of the views are breathtaking making all the sweat, profanity and walking your bike up the steeper hills well with it!
Also, coffee trail isn't as good as people say it is. Maybe I just rode it at a bad time but since it is a horse trail there was a lot of loose dirt making it very slow going and frustratingly exhausting.
Overall, if you find yourself on Mackinac Island and want to get explore more of the unpopulated areas, the mtb trails are a great option. Only saw 2 other mtb bikers on the trails and I was riding for about 2 and a 1/2 hours on a busy summer day.
| ThankLock your fork, it's best to stay on the double track. I was pretty excited for the mountain bike trails based on the quality of Mackinac's double tracks and paved trails but unfortunately they didn't meet my expectations. I took the Tranquil Bluff trail starting from English Landing ( as suggested from previous comments ) and immediately noticed how eroded and overgrown the trail was, it was obvious the local rangers hadn't been on these trails in a while. Never the less, I kept my hopes up and trudged on. After getting lost a few times and meeting plenty of inexperienced tourists on cruisers I finally got back to the Tranquil Bluff trail. It was then that I came to probably the biggest reasons I gave this trail such a low rating, the trail became to overgrown to discern, my ride become a trail walk while I picked up litter, and I was forced to portage over and under dozens of fallen trees. Overall, the trail was obviously neglected by the local forest rangers and loved by frat parties, a must go for any philanthropist with a saw and a trash bag interested in some good ole trail clean up!
| ThankThis trail gets a 4 star rating for me because i love Mackinac. Its great in the summer to ride, then chill out in one of the local establishments for a cold beverage and live music.
Trail difficulty is minimal, I did encounter lots of downed trees and limbs. It's a popular vacation destination, so the trail technical difficulty is low. If you don't bring your own bike, rent one and explore.
| ThankA super fun pre-tourist season trail system. The month of may, early June one can have the wildflower trails to yourself. Any of the hores trails make for good single track.
| ThankTranquill Bluff has got to be one of my favorite single track rides. Some gnarly sections in the beginning. Never going up or down for too long so this trail has got some good flow.
| ThankSome of the trails are nice easy riding while some of the trails are difficult to walk through, personally i have ridin pretty much all of them and have only ate sh!t in a few spots. But if you were wondering if there is decent Mt. Bike riding on Mackinac Island the answer is yes! Come on over and check it out!
| ThankThis whole island is a great place to ride. Great views, single tracks, wider trails, and roads with no motorized vehicles!
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