GETTYSBURG, Pa. — The commemoration of this year’s milestone anniversary of the Battle of Gettysburg will include amenities that soldiers would have relished 150 years ago.

A groomed path to the top of Little Round Top. Expanded cellphone coverage. Dozens of portable toilets.

The National Park Service and a cadre of community organizers are busily putting the finishing touches on preparations for the commemoration of the pivotal battle of the American Civil War that cemented this small Pennsylvania town’s place in U.S history. Tens of thousands of visitors are expected for a 10-day schedule of events that begin June 29.

“I think we’re ready,” Bob Kirby, superintendent of Gettysburg National Military Park, said in a recent interview . “We’re ready for what the world would like to see.”...