Another in a series of historic hiking trail highlights leading up to the Acadia Centennial

Dating back to the late 1800s, the trail to South Bubble and its precariously perched 100-ton Bubble Rock has lured scientists, artists, outdoor enthusiasts and first-time visitors for generations, long before the area was protected as Acadia National Park.

Eons of geological forces are laid bare there if you know what clues to look for, as a ranger-led “Mountain Mysteries” program reveals during the summer months.

In fact, Bubble Rock was one of those clues that led 19th century scientist Louis Agassiz to theorize that massive glaciers once covered the earth and pushed big boulders around, not floods of biblical proportions as had been previously thought.

The moderate 1-mile round-trip hike starts from the Bubble Rock parking area and Island Explorer bus stop and takes you first along the Bubbles Divide Trail, the historic route that goes between the South Bubble and North Bubble, then up the lower of the twin mountains.

Near the summit of 766-foot South Bubble, a short side trail takes you to Bubble Rock. While the rock appears a small speck on the side of South Bubble from the Park Loop Road, up close it’s bigger than a cargo van.

For first-time and return visitors to Acadia National Park, it’s popular to try to push Bubble Rock. Take a photo for the memory books, as we’ve done with our nieces.

Close inspection of the rock reveals large black and white crystals, unlike the native pink granite of Acadia. In fact, Bubble Rock is of the same stuff as bedrock from about 40 miles away, near Lucerne.

The rock is just one of many glacial erratics – boulders transported for miles and left by retreating glaciers – found throughout Acadia.

The view from South Bubble provides another geology lesson. If you follow the trail south a short distance from the peak, grand views open up of the glacially formed Jordan Pond, and the moraine that Jordan Pond House sits on.

It’s another reminder of nature’s scale, and the small speck that human history is.