Ascend to where a massive granite monolith juts into the sky, then pass a swamp where another huge boulder has sat as a silent witness for millennia.
Big and Little Agassiz Rocks are dramatic examples of giant boulders plucked from bedrock and carried far away by the last glacier. As the glaciers scoured this landscape, the mass of bedrock forming the hill proved more resistant than the surrounding soil, forcing the bottom of the glacier up and over the hill. The north side was smoothed and the south side left steep and rugged as the glacier broke off chunks of rock as it passed.
Make your acquaintance with these geologic marvels by ascending the property’s 1.5-mile loop trail up Beaverdam Hill. The moderate hike leads to an inimitable sight: Little Agassiz Rock, a giant granite monolith silhouetted against the clouds. A short distance away, in a small shrub swamp past the other boulders, perched on the edge of this glaciated upland, rests 30-foot-tall Big Agassiz Rock. Nobody knows how far below the ground it is buried.
After long periods of rain, take extra caution: when the water table is high, the area surrounding Big Agassiz Rock can be flooded.
FREE to all.
This property is open during normal hours. The Trustees asks that visitors follow social distancing guidelines for the health and safety of all. Please note: all buildings and inside areas remain closed on all properties. For more information about our response to COVID-19, please click here.
When to Visit
Open year-round, daily, sunrise to sunset. Allow a minimum of 1 hour.
Manchester-by-the-Sea, MA 01944
From Rt. 128 (exit 15), take School St. north for 0.5 mi. Entrance and roadside parking (10 cars) on right.
Free trail map distributed from bulletin board in the parking area. Please understand that supplies periodically run out.
We recommend that you take a photo of the map on your phone so you can refer to it during your visit, or download a trail map before you head out.
We want you to experience Trustees reservations to their fullest, whether you're spending time with friends and family or seeking quiet time by yourself.
Castle Hill Illuminated allows you to imagine yourself a guest at the Crane family’s famed summer home in 1929.
The Trustees honors all frontline workers with free admission to almost any Trustees property one day of every month.
Beautiful easy hike for those who are ready to get out of their car or away from being a tourist in Boston.
– KarenHawkinson, Trip Advisor Review
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