Visitors to the Fort Pitt Blockhouse can see and touch some of the same stones, bricks and logs that were used when it was built in 1764.
Work began Wednesday to make sure that future visitors will have that same experience in what is the oldest documented building in Pittsburgh.
The Fort Pitt Society, which owns the historic structure, said the 10-month preservation and restoration project is being funded by an anonymous donor and the Colcom Foundation. The work will cost about $140,000, spokeswoman Maureen Mahoney Hill said.
The blockhouse was built as part of Fort Pitt, which was located at what is now Pittsburgh's Point State Park. The fort, constructed in the last years of the French & Indian War, was the largest British fortification in North America.
Much of the stone foundation, bricks and timber in the two-story blockhouse are original. The mostly solid walls of the structure are punctuated by two rows of wooden-framed gun ports that gave defenders stationed in the blockhouse a 360-degree view around the building.
"Our highest priority is to insure the stability of the gun loop timbers," project architect Ellis Schmidlapp, of Landmarks Design Associates, said in a statement.
A company called TUV Rheinland Industrial Solutions Inc. will carry out radiographic inspections of the original wood in the blockhouse. The entire effort will be done to "assure that this preservation project is managed conscientiously to preserve the maximum amount of the original timbers," Mr. Schmidlapp said. The first priority will be conservation.
The radiography testing is designed to reveal any density variations inside the wood. The results of those tests would provide warning of deterioration of the timber around the gun loops, according to Frank Buffington, eastern operations manager for TUV Rheinland. Preservation experts then would determine whether reinforcing filler material would be needed to preserve the original wood.
Any preservation work on the gun loops would have to wait until warmer weather in April. Masonry restoration and French drain repairs are scheduled for completion in August. Interior work would be finished by the end of October.
Work on the blockhouse, which has stood in the same location for almost 249 years, will be completed in time for the 250th anniversary of its construction.
The soldiers in the blockhouse and other similar defensive outbuildings, known as redoubts, kept watch over the fort's exterior and provided its first line of defense. The rows of small gun ports would have allowed soldiers to fire their muskets at enemies trying to attack. Fort Pitt never faced hostile fire after the blockhouse was built.
After Fort Pitt was demolished in the 1790s, the blockhouse was used for multiple purposes, including serving for many years as a private residence. Given to the Fort Pitt Society by philanthropist Mary Schenley in 1894, it has been open to the public for more than a century. The society is part of the Pittsburgh Chapter of the Daughters of the American Revolution.
Visitors will be able to tour the interior of the blockhouse during most of the period while the preservation project is under way, Ms. Hill said. "We will try to keep it open as much as possible," she said. "Visitors will be able to watch the process."
Winter hours for the blockhouse are 10:30 a.m. to 4:30 p.m. Friday through Sunday. Admission is free.
"The blockhouse is quite literally where Pittsburgh began," Joanne Ostergaard, a member of the Fort Pitt Society and coordinator of Block House 250, said.
"It is our goal to ensure that it continues to stand as an enduring symbol of American strength and tenacity so that future generations can know and appreciate the important role our region played in history."
Len Barcousky: email@example.com or 412-263-1159.