Olmsted NHS summer 2017 programs include free walks throughout the season, no reservations needed.  On Sunday, July 30 beginning at 1 pm you are invited to Invasion of the Aliens Part III. This interpretive walk focuses on the natural history of the Wilderness in Franklin Park with a focus on invasive plants. Please wear hiking or running shoes. To RSVP or learn more, and for directions to start point, please call (617) 566-1689 ext. 221. For a complete list of programs visit https://www.nps.gov/frla/special-events.htm