Most N.D. historic sites open May 16

North Dakota’s state historic sites will open or expand hours for the summer season, beginning May 16 and continuing through Sept. 15. The historic sites opening for the season include Gingras Trading Post near Walhalla; Fort Abercrombie, and its interpretive center, near Fargo and Wahpeton; Fort Clark Trading Post near Washburn; and Whitestone Hill near Kulm.