Cambridge is a city in and the county seat of Guernsey County, Ohio, United States. It lies in southeastern Ohio, in the Appalachian Plateau of the Appalachian Mountains. The population was 11,129 at the 2010 census. It is the principal city of the Cambridge Micropolitan Statistical Area. Cambridge is well-known among glass collectors as being the location for the Cambridge Glass, Boyd Glass and Mosser Glass plants. The Cambridge area is also famous for its "S" shaped bridges, dating back to the building of the National Road in 1828. It is located adjacent to the intersection of Interstates 70 and 77, which the Ohio Department of Transportation proclaimed in 1969 to be the world's largest interchange in terms of land area.
In 1796, Col. Ebenezer Zane received funds to blaze a road suitable for travel by horse through the Ohio wilderness from a point on the Ohio River opposite Wheeling, Virginia (now Wheeling, West Virginia) to another point opposite Maysville, Kentucky. Where this road, known as Zane's Trace, crossed Wills Creek, a ferry was established in 1798. This was followed by the first bridge authorized by the legislature of the Northwest Territory, built in 1803. The land on which part of Cambridge stands was granted to Zaccheus Biggs and Zaccheus Beatty by the government in 1801. A settlement grew up at the creek crossing. The town of Cambridge was platted there in 1806. Both Cambridge, Maryland and Cambridge, Massachusetts have been speculated by historians as having inspired the naming of the town. Also in 1806, another group of early settlers from the Isle of Guernsey in the English Channel pitched camp in Cambridge, reportedly because the women in the party refused to move on. The county for which Cambridge serves as the county seat was later named in honor of its many settlers from Guernsey.
In 1828, the federally built National Road came through Cambridge. The first railroad arrived in 1854.