This two-hour National Park Service walking tour on Saturday, May 16, from 9 – 11, will examine the multifaceted history of the Fens focusing on its transformation from “the foulest marsh and muddy flats to be found anywhere in Massachusetts” into an urban oasis of greenery. Afterwards, we will visit one of the many Boston cultural institutions that migrated to the surrounding neighborhood following the Fens’ creation, Boston Symphony Hall. REGISTRATION is required – please click on to http://www.nps.gov/frla/planyourvisit/walks-and-talks.htm. Aerial view from www.pressleyinc.com.