The traveling exhibition, “Torn in Two: 150th Anniversary of the Civil War,” opens Thursday, April 4, at the University of Southern Maine Osher Map Library and Smith Center for Cartographic Education, Portland.

On April 4, there will be a reception and exhibition preview from 6 to 6:30 p.m.

Curator Ronald E. Grim will give a presentation titled “Torn in Two: Remembering the War through Maps” from 6:30 to 7:30 p.m.

An RSVP by Friday, March 29 is needed for the April 4 presentation. For more information and to RSVP, contact the Osher Map Library at 780-4850 or oml@usm.maine.edu.

Grim is curator of the Norman B. Leventhal Map Center at the Boston Public Library, where this exhibition originated.

The exhibition will be open from Tuesday, April 2 through Thursday, August 22.  Exhibition hours are from 1 to 4 p.m. Tuesdays through Thursdays and is free and open to the public. Free parking is available at USM’s parking garage off Bedford Street.