[8] In December 2020, the Park Service received funding to purchase an additional 3,000–4,000 acres (4.7–6.3 sq mi) of land.

[9] A visitor center called the Tekαkαpimək Contact Station was inaugurated in August 2024 with a design inspired by Wabanaki culture and history.

"[11] It was suggested that President Donald Trump could act to reverse the creation of the monument, a move local opponents wanted him to consider.

Senators from Maine, Angus King and Susan Collins, wrote a letter to President Obama outlining “serious reservations” about the proposal.

[17] Human settlement in the region dates back 11,000 years, with Native peoples having relied on the woods and its waterways for their livelihood and even transportation.

In the lands west of the Penobscot River's East Branch, volcanic rock from the Devonian period, mostly Katahdin granite and some Traveler rhyolite, is prevalent.

The oldest rock in the monument, a light greenish-gray quartzite and slate from the early Cambrian period, which is 500 million years old, can be observed along the riverbank of East Branch at Grand Pitch (a river rapid).