The Maine Historical Society will be bringing a 250-year-old copy of the Declaration of Indpendence to locations in every Maine county this year, in honor of the country’s birthday.

The tour dates and locations were announced Thursday morning at the historical society’s Brown Research Library on Congress Street in Portland. The document is one of 26 surviving copies of an early version of the declaration, known as a Dunlap Broadside and printed by a shop in Philadelphia soon after it was written, said Steve Bromage, the society’s executive director.

“As we headed toward the 250th, one of the things we were thinking about was how do we really include people around the state in a truly meaningful way,” said Bromage.

The document will first be on public view at the Maine Historical Society in Portland from March 13 through July 4 as part of an exhibit called Pathways to Freedom: Maine Stories from the American Revolution. The exhibit will focus on six Mainers’ experiences during that time.

Beginning in mid-July, the document will then be on exhibit, for free, for two or three days at a time in locations in every Maine county. The tour will start July 17 at the Maine Maritime Museum in Bath and end Oct. 31 at the Bowdoin College Museum of Art in Brunswick.

The Dunlap Broadside copy of the declaration has been in the historical society since 1906, and was donated by John Samuel Fogg, a doctor in Eliot who collected autographs, among other things. It was authenticated in the early 1990s, Bromage said, and is similar to a copy that Harvard University has.

John Dunlap, the official printer to the Continental Congress in Philadelphia, began setting the type for copies of the Declaration on the night of July 4, 1776, when it was largely written but not fully signed. The congress voted to have early copies of the document sent to assemblies, conventions, committees and military commanders.

About 200 copies of the Dunlap Broadside were printed and sent around the colonies. The Maine Historical Society’s version, which has John Hancock’s name on it but no other signers, is one of 26 known to still exist, Bromage said. He said that the broadsides were meant to spread the word about the congress’ intentions, in the days before any sort of instant communication.

“It was kind of the tweet of its day. It was the way to get information out as quickly as possible,” said Bromage.

The historical society’s Dunlap Broadside is kept most of the time in a secure, undisclosed location that’s climate controlled, Bromage said. The last time it was on public display, as part of an exhibition at the Maine Historical Society in Portland, was five or six years ago, Bromage said.

Last year, as the historical society’s staff began thinking of ways to celebrate the nation’s 250th anniversary, the idea of bringing the Dunlap Broadside to people around the state came up. Bromage said he was giving a talk in Camden when somebody mentioned the document and asked, “Why can’t you bring it with you?” After that, Bromage and other staff members started talking about the logistics of making a tour happen, and began raising money to fund it.

Here is the full list of tour stops and dates:

• Maine Maritime Museum, Bath, July 17-18
• Bigelow Laboratory, Boothbay, July 24-25
• Brick Store Museum, Kennebunk, July 31-Aug. 1
• Camden Public Library, Aug. 7-8
• Belfast Free Library, Aug. 14-15
• Abbe Museum, Bar Harbor, Aug. 21-22
• Tides Institute & Museum of Art, Eastport, Aug. 28-29
• Foxcroft Academy, Dover-Foxcroft, Sept. 4-5
• University of Maine at Presque Isle, Sept. 11-12
• Bangor Public Library, Sept. 18-19
• Margaret Chase Smith Library, Skowhegan, Sept. 25-26
• University of Maine at Farmington, Oct. 2-3
• Norway Memorial Library, Oct. 9-10
• Maine Museum of Innovation, Learning and Labor, Lewiston, Oct. 16-17
• Maine State Cultural Building-Maine State Library, Archives and Museum, Augusta, Oct. 22-23
• Bowdoin College Museum of Art, Brunswick, Oct. 30-31