Editing Port Deposit, Maryland (section)

===Granite and bridges===
[[File:Port Deposit MD Gerry House.JPG|left|thumb|upright=1.2|The Gerry House was built in 1812. [[Gilbert du Motier, Marquis de Lafayette|Lafayette]] was entertained here in 1824.]]
The first attempts to bridge the Susquehanna in Maryland were made by the Port Deposit Bridge Company, incorporated in 1808. Its attempts failed, so the Legislature in 1812 authorized another company to proceed. After completing a survey in 1813, which included the first written reference to Port Deposit, the company proposed a location that complied with the law but was longer than necessary. After petitioning for relief, the company was allowed to route the bridge closer to the falls, allowing it to be {{convert|1000|ft|m}} shorter. The [[Port Deposit Bridge]], a wooden [[covered bridge]], was built just north of Port Deposit during 1817 and 1818. Put into service in 1818, it was the earliest bridge crossing of the Susquehanna. Rebuilt after a span burned in 1823, it remained in service until 1857.
<ref name="Johnston" />

A {{convert|4|acre|m2}} site at the north end of Port Deposit was committed to quarrying "granite." (actually [[gneiss]])<ref>The formation is known by geologists as [[Port Deposit Gneiss]]. This gneiss has a granite-like appearance and had a dark color and an even, granular texture which made it easy to work; it was prized as a building stone.</ref> for bridges. The general area had been the site for granite quarrying before the bridge was constructed as there was use of this specific granite in buildings constructed before the [[American Revolutionary War|Revolutionary War]]. This granite can be seen in many of the distinctive buildings in Port Deposit today.<ref name="Susq" /><ref name="Johnston" />

Quarries were also opened here in 1829 by the proprietors of a competitor canal, the [[Susquehanna and Tidewater Canal]], between [[Havre de Grace, Maryland|Havre de Grace]] and [[Wrightsville, Pennsylvania]], for canal construction projects routed along the opposite bank of the Susquehanna.<ref name="Susq" /><ref name="Johnston" />

These quarries continued in service well into the 20th century. Port Deposit gneiss was used in:<ref name="Susq" />
* Many houses and five churches in Port Deposit
* Schools such as the [[U.S. Naval Academy]], [[Haverford College]] and [[Catholic University of America]]
* [[Fort McHenry]], [[Fort Delaware]] and [[Fort Carroll]]
* Public buildings like the [[Boston Public Library]] and the [[Treasury Building (Washington, D.C.)|U.S. Treasury Building]]
* Public works such as the [[Concord Point Lighthouse]], [[Lincoln Tunnel]] and the [[St Augustine]] seawall