One of North Carolina’s Last Covered Bridges
Bunker Hill Covered Bridge | Catawba County, NC | c. 1894-95
The Bunker Hill Covered Bridge in Catawba County, North Carolina, is a rare surviving example of 19th-century covered bridge engineering and the only remaining improved lattice truss timber bridge patented by General Herman Haupt in 1839. Haupt, a renowned civil and military engineer, author, and inventor, revolutionized bridge construction with his innovative designs, detailed in his influential 1851 book General Theory of Bridge Construction. Covered bridges, valued for their durability and protection from the elements, were vital to early American infrastructure. The Bunker Hill Covered Bridge is the only remaining example of the improved lattice truss timber bridge, patented by Haupt (1817–1905), standing as a testament to his engineering prowess.
Why Covered Bridges?
Uncovered wooden bridges typically had a lifespan of 15–20 years. However, adding a roof and sides could extend their lifespan to over 100 years. Covered bridges became popular as their design protected the wooden structures from the elements—rain, sleet, snow, and sun.
The construction of these bridges often resembled a barn raising, with local farmers and communities contributing to the effort. This led to their characteristic barn-like appearance, though they utilized various truss systems. A truss is a triangular framework of timbers, where each timber supports the others. Together, the system distributes weight and stress evenly across the bridge span.
The First Covered Bridges
In 1805, the first covered bridge in America was built in Philadelphia, Pennsylvania, across the Schuylkill River. It spanned 550 feet with three sections. North Carolina’s first covered bridge was built in 1818 across the Yadkin River near Salisbury by a local plantation owner, using Ithiel Town’s lattice truss design. By the 19th century, there were thousands of covered bridges across the United States, with hundreds in North Carolina alone.
A Covered Bridge in Catawba County, North Carolina
In 1894, Catawba County decided that a more substantial bridge was needed to cross Lyle’s Creek. Back then, there was no dedicated roadwork agency, so county commissioners assigned road-building tasks to local farmers and residents who would use them. That same year, local landowners hired Andy J. Ramsour, the keeper of the Horse Ford Covered Bridge over the Catawba River in Hickory, North Carolina. Ramsour, along with Eli Kale, George Moller, Cain Bost, and Electious Connor, built the bridge in 1895, likely following a design Ramsour found in a popular bridge-building book published by Herman Haupt in 1851. (You can scroll to the bottom to learn more about Herman Haupt, Union General and bridge builder).
The Bunker Hill Bridge was originally constructed as an open span and the bridge was covered-in five years later. Made of oak wood and assembled with wooden pins (trunnels) instead of nails, it initially had a wooden shingle roof. The shingles were replaced with a tin roof in 1921. In 1994, a major restoration stabilized the structure.
What’s in a Name?
The name “Bunker Hill” comes from the nearby Bunker Hill Farm, operated by the Shuford and Lowrance families since the early 1800s. The bridge is also near the site of an early post office bearing the same name.
Island Ford Road and Lyle’s Creek
Bunker Hill Bridge was part of Island Ford Road, a former Indigenous trail that played a significant role in the western development of North Carolina. During the colonial period, this road was used to transport British prisoners of war after the 1781 Battle of Cowpens.
As one observer noted, “The Morgan Army, with hundreds of prisoners and captured horses and wagons, stretched more than two miles as it approached the Island Ford.” By the mid-20th century, Island Ford Road became a major thoroughfare as part of U.S. Highway 64/70.
In the 19th century, Catawba County was home to at least 10 covered bridges. Many were destroyed during the devastating floods of 1916 and 1940, while others were phased out during the state legislature’s “Good Roads Movement” of the 1920s. Today, only two covered bridges remain in North Carolina, located in Catawba and Randolph Counties.
Who was Herman Haupt?
The Bunker Hill Covered Bridge was built based on the designs of Herman Haupt and today, is the only remaining example in the world of a Haupt Truss Bridge built from wood.
Haupt was a General in the Union Army and in 1862, the Secretary of War called on Haupt to assist in the reconstruction of railroads destroyed during the Civil War. Haupt was able to both rebuild the rail system and organize an efficient rail operation to resupply the union. In nine days, using troop labor, Haupt rebuilt the Potomac Creek Bridge which had originally taken one year to build. Visiting the site of Haupt’s astounding accomplishment, President Lincoln reported to his cabinets that the bridge was “the most remarkable structure that eyes ever rested upon. Haupt has built a bridge across Potomac Creek, about 400 ft long and nearly 100 ft high, over which loaded trains are running every hour.”
In 1851, Haupt published his book, “A General Theory of Bridge Construction”, detailing his patent which improved upon the lattice trust design. Haupt wanted to discover a formula for determining the weight distribution and capacities of bridges. This book, detailing his discoveries, became a standard text for civil engineering at the main engineering schools of the era.
