The Al Retelle Reservation is named for Albert R. Retelle (1930-2014), a resident of Andover and an avid conservationist. Al Retelle encouraged the Town of Andover to create a Conservation Commission upon the initiation of the Wetlands Protection Act and became the first Chairman when the Commission was founded in 1960.

The Al Retelle Reservation is 64 acres in size and supports a diverse range of habitats that encourage critical wildlife biodiversity. Grasslands, wetlands, mature woodlands, and early successional habitats can all be found throughout the reservation, each characterized by specific vegetation and wildlife species.

Historically, the Pennacook lived along this portion of the Merrimack River before European colonization of the area. European settlements displaced these native communities and the old-growth forest along the river was cleared for agriculture. However, this farmland was gradually abandoned over the last hundred years, allowing succession to occur. Early successional vegetation is in short supply across Massachusetts, but it creates critical habitat for wildlife species such as chestnut-sided warblers and the New England cottontail. This transition from field to forest can be observed in action on the Al Retelle Reservation to this day.

The Merrimack River is a 117-mile-long river in the northeastern United States. It rises at the confluence of the Pemigewasset and Winnipesaukee rivers in Franklin, New Hampshire, flows southward into Massachusetts, and then flows northeast until it empties into the Atlantic Ocean at Newburyport. From the point where the Merrimack turns northeast in Lowell, Massachusetts onward, the Massachusetts–New Hampshire border is roughly calculated as the line three miles north of the river.

The AllTrails website has a description and map of a hike at Retelle Reservation.