Once home to more than a dozen stone arch masonry bridges, Hillsborough now has five of these gems,
four of which are used everyday to support auto, bike and foot traffic.
These bridges are registered as historic structures by the Historic American Building Survey, part of the National
Park Service. Most recently they have been recognized as a National Historic Civil Engineering Landmark,
the second in New Hampshire, after the Cog Railway.
Stone arch bridges were a solution to the weakness of timber bridges and were especially suited
for withstanding frequent flooding in the steeply sloping New Hampshire streams and rivers. Historical
records reflect the repeated
destruction and rebuilding of many of the earlier wooden bridges, leading townspeople to seek more rugged
and enduring forms of construction.
At the time, lime mortar did not have sufficient strength to withstand the arch stresses, often failed
to harden in the interior arch walls, and did not set in water. By a more careful cutting and fitting
of stones, it was possible to make
stronger stonework than could be made with use of the conventional lime mortar of the period; hence
the development of the technique of known as "dry masonry."
Gleason Falls Bridge © Karen E. Booth
The stone arched bridges are believed to have been the work of Scotch-Irish stonemasons who emigrated
to Hillsborough in the 19th century. Selectmen Hiram Monroe argued that the bridges be built of
stone to last, and that they have. Each of these lovely examples of bridge building craft is still
in place with original keystones and held together without the benefit of mortar.
A brief tour by car or bike can take you to all of them, or a walking tour along the scenic Beard's
Brook will show you three of them. In warm weather, you can finish your tour with a refreshing dip
in the Old Swimming Hole. A public
beach, bathhouses and barbecue grills are available, along with ample parking.
Jones Rd. Bridge © Karen E. Booth
The first bridge is the magnificent double arch bridge over the Beard Brook at the meeting of the
Beard and Jones Roads, known as the Old Carr Bridge, built by Captain Jonathan Carr in 1840, and allegedly
paid for with counterfeit money. This mortar-free graceful span breaches the brook and is a popular fly fishing spot.
North up Beard Road looms the mighty Gleason Falls Bridge, which contains an impressive cascade of water.
Located near the junction of Gleason Falls and Beards Brook Roads, this inviting spot offers
picnicking, wading, and fishing. The falls rush under this venerable stone bridge from the 1840s,
and are at their best in the spring.
Old Carr Bridge in Winter © Karen E. Booth
Another fine stone span stands up the road and to the left on the Gleason Falls Road, at the site of
one of the town's first gristmills. This bridge is shrouded in mystery as to when it was built and by whom.
The clever craftsman built a
unique bridge, which actually consists of a causeway and two bridges over Beard's Brook. The span to
rise ratio of each arch is what makes this one unique. While most conventional arches would be semi-circular
with a span to rise ratio of
2.0, as it is with one arch, the ratio of the other arch is a staggering 4.37!
Returning south down the Beard Road, and across Rt. 9/West Main Street to the Saw Mill Road we come on
the quaint stone bridge south of the Lower Village, a grouping of early houses, surrounded by
forests, that is both rich in character and history. Saw Mill Road Intersects the Second NH Turnpike,
which was once the main road from Claremont to the
south.
To the left of this intersection you will find the bridge that was built in 1864 for $100. This bridge
provided reliable transportation along the vital route from the northeast to Boston. This particular
road was so important that an
up-and-coming Benjamin Pierce built his fine new house and tavern on it. In that very house he raised
a son who would go on to become a U.S. President; Franklin Pierce.
Jones Rd. Bridge © Karen E. Booth
It is said that the finest Hillsborough stone arch bridge was built in 1866 by Rueben Loverin,
known as the Sawyer Bridge. Despite some modifications made for commercial use, the bridge retains
its integrity. It can be found at the junction of Route 202 and West Main Street, where it has had its
traffic diverted and will soon be home to a small garden park for picnicking. This bridge once included
a third arch more distanced from the other two, at its south end, which served as an opening allowing cattle
to pass beneath and travel between the neighboring farm's fields. In 1988, days before the bypass bridge
was to open, the third arch collapsed, necessitating an earlier opening of the new bridge.
We hope you enjoy Hillsborough's unique relics of New England's history, and wish you
many safe returns.
Photos Copyright by Karen E. Booth