IOWA CITY, Iowa – The U.S. Army Corps of Engineers is celebrating National Public Lands Day at Coralville Lake, Saturday, September 29. Festivities will include a park cleanup and an outdoor concert. Volunteers of all ages are invited to help with the park cleanup from 1-4 p.m., trash bags and gloves will be provided. Following the cleanup, all registered volunteers will receive a voucher for free entry into a federal park or a single night of camping at Coralville Lake. To register, call 319-338-3543, ext. 6308 or e-mail Coralville.Lake@usace.army.mil. Onsite registration will also be available the day of the event at the Coralville Lake Visitor Center between 10 a.m. and 1 p.m.