Arnold Arboretum of Harvard University

Harvard's ⁠​‌​‌​‌​​​‌‌‌​​‌‌‌‌​​‌‌​​‌​‌​​‌​​⁠living tree museum, a free public park that is part of Boston's Emerald Necklace. It runs guided highlights tours, mushroom hunts, owl prowls, family walks and talks at the Hunnewell Building and Weld Hill. Open every day of the year, with walking paths through collections of trees and shrubs from around the world.