A 3-mile underwater preserve that runs along the volcanic shoreline, Agate Harbor is a hot spot for geological wonders.
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- Don't Forget
- Check the weather before you set out on the water, as sudden gusts can quickly change conditions on Lake Superior from peaceful to precarious.
- Best Time to Go
Agate Harbor also features beautiful inlets, barrier islands, and magnificent reef formations that call to mind the coastline of a tropical island.
Launch your kayak or canoe from the pebbly beach at Esrey Park and set off northward—with a friendly wind, you’ll soon arrive at the finger bays that reach out from the base of Brockway Mountain.
The shallows here are prime spots for finding agates of exceptional size and beauty, as well as yooperlites, quartz, and other rock treasures.
Fresh Coast Tip
To get the most out of this experience, we recommend chartering a tour with a local outfitter who can safely guide you to the most interesting features of this unique nature preserve.
If the water is calm, you might get a glimpse of the remains of the City of St.Joseph, a 254-foot barge that fell victim to the reef in 1942 and now lies just 30 feet below the surface.
Finish your tour with a visit to the Arch Rock, a massive basalt formation with the largest span of any arch on the north end of the peninsula. Make sure to bring a water-safe housing for your camera-you won’t want to miss the photo opportunity of crossing through this one-of-a-kind Lake Superior landmark.
Between the fresh pine-scented air, the wild and lonely terrain, and the staggeringly clear view of the lake’s rocky depths, this is one of the Keweenaw’s most exceptional experiences.
Photo: Drew Mason / @drewmason