There are no hidden caches in national parks, but one can still search for treasures. There are long-established virtual caches and earthcaches that will lead the seeker to unique locations within the parks. At Acadia the park rangers themselves have created a series of earthcaches that eventually leads to getting a special stamp, which I had placed in my National Parks Passport. For an article on this special cache and more background on geocaching, see Natural Resource Year in Review–2006.
The search for the Story of Glaciers and how they created the land that is now Acadia National Park begins along Somes Sound, a fjard or glacially-carved embayment that is drowned by the sea. It is not technically a fjord, which is how most of the guides and tourist literature refer to it.

Somes Sound--Earthcache #1
There are four other stops on the trail to finding the secret answer that will earn the cacher the special stamp. In order to avoid giving away the final question and answer, I won’t describe all of the stops.
Two of the stops require some hiking. The hike to the top of a Bubble is the most challenging, but it is only about 1/2-mile to the top or one mile round trip. The park classifies the trail as moderate, probably for elevation change. The elevation of the Bubble is somewhere between that of Gorham Mountain (525′) and Beech Mountain (839′) (which I described in an earlier post), but the trail is much shorter than either. I would highly recommend good foot wear, although I saw teens in flip-flops and Europeans in leather-soled dress shoes.

View from Atop South Bubble Mt
The top of the Bubble is a great place to see how a glacier scoured the Cadillac Mountain Granite of the mountain and left behind as it receded pieces of Lucerne Granite that was formed 30 miles northwest of Mount Desert Island.

Exposed Cadillac Mountain Granite Atop South Bubble
A waymark for the erratic has been registered, along with a brief trail description and some spectacular photos, at
waymarking.com.

Glacial Erratic of Lucerne Granite
There are several non-park sponsored earthcaches on Mount Desert Island, but I only went in search of one–Ellsworth Schist. Needless to say, this cache is about another kind of rock–the oldest on Mount Desert Island.

Ellsworth Schist--a layered metamorphic rock

Quartz layers
Located on the west side of the island not far from the Seal Cove Auto Museum, there’s more to see than just rock.

Seal Cove at low tide

At anchor in Seal Cove
There are also five virtual caches within the park boundaries that will take you to Bass Harbor Head Lighthouse, Otter Point, Great Head, the top of Cadillac Mountain, and Jordan Pond–all of which I’ve covered in earlier posts.
Outside the park’s boundaries there are numerous traditional caches. I looked for four along my paths of travel. All were relatively easy finds. One involved hiking the unmaintained Seaside Trail from Jordan Pond house–a perfect excuse for indulging in popovers afterwards.

Popovers at Jordan Pond House