Question: William F Romain led a team in an investigation a effigy mound in Adams County, Ohio, that is how long?

Context paragraphs:
Friendship Mound: Friendship Mound (also known as Rocky Bluff) is a castellated mound located just north of the village of Friendship, Adams County, in the U.S. state of Wisconsin.  It is the highest point in Adams County, with an elevation of 1290 - and a prominence of 330 ft <ref name="http://www.peakbagger.com/peak.aspx?pid=22732">Friendship Mound - Peak Bagger</ref>—though the adjacent Roche-A-Cri Mound in Roche-A-Cri State Park is not far behind).  Friendship Lake is also adjacent to the mound, across Wisconsin Highway 13.

Cranberry Creek Archeological District: Cranberry Creek Archeological District, also known as Cranberry Creek Mound Group, is an ancient American Indian burial mound site from circa AD 100–800 near New Miner, Wisconsin, United States.  It is three miles east of Necedah National Wildlife Refuge in Juneau County.  It is part of the "effigy mound culture" of native peoples in Wisconsin, who practiced the "respectful burial of their dead".

Effigy mound: An effigy mound is a raised pile of earth built in the shape of a stylized animal, symbol, human, or other figure and generally containing one or more human burials.  Effigy mounds were primarily built during the Late Woodland Period (350-1300 CE (current era)).  Conical and linear mounds, the predecessors of effigy mounds may date from as far back as 700 BCE (before the current era).  They remain places First Peoples frequent to visit and speak with ancestors, to put down tobacco and to give thanks.  These sites are primarily visited by Hochungra (pl.  of Hochunk) people whose ancestors likely built the great majority of them, though they are also visited by people from other original indigenous nations such as Anishinaabe (Ojibwe), Kikapu, Oneida, Menominii who reside in Wisconsin and surrounding areas.  There also remains the possibility that a greater diversity of First Peoples such as ancestors of those named nations may have contributed to building some percentage of the mounds.  That is to say that ancestral Hochunk likely popularized the form and other groups may have adopted the practice of building effigy mounds from having observed the Hochunk ancestors methods and aesthetics surrounding their construction.

Schmucker Hall: Schmucker Hall is an American Civil War site listed on the National Register of Historic Places in Adams County, Pennsylvania, that was constructed as the original Gettysburg Theological Seminary building.  Used as both a Union and Confederate hospital during the 1863 Battle of Gettysburg, the facility served as the seminary's main building from 1832 to 1895, then as a dedicated dormitory for students until 1951.  In 1960, it was leased by the Adams County Historical Society.  Beginning in 2006, the Historical Society, along with the Seminary Seminary Ridge Historic Preservation Foundation, rehabilitated the building for adaptive reuse as the Seminary Ridge Museum www.seminaryridgemuseum.org .  The Adams County Historical Society moved into the nearby Wolf House on the seminary campus preceding the renovation.  In 2013, on the 150th anniversary of the battle, the Seminary, the Adams County Historical Society and the Seminary Ridge Historic Preservation Foundation opened the building as the Seminary Ridge Museum.  The Museum houses displays about many different aspects of the battle, the seminary, the town, and the civil war, and the struggle among faith groups over slavery, as well as offering tours of the cupola.  The exhibit and museum have earned international, national and regional awards and the rehabilitation achieved LEED Certification in 2013.

Intaglio (burial mound): Intaglio (from Italian: "intaglio" ] ) is a term from art applied to burial mounds that refers to a design cut into a hard surface.  In this case, the burial mounds have designs cut into the ground, though "intaglio" broadly applies to burial mounds which are raised above the natural surface of the terrain.  There are much more rare forms where they are left as indents below the natural terrain.  These are typically in some effigy shape such as the Panther Intaglio Effigy Mound, which can be seen in Fort Atkinson, Wisconsin, where it is the last remaining intaglio mound in the state.

Man Mound: The Man Mound is a prehistoric humanoid earthwork located in Greenfield, Sauk County, Wisconsin, east of the city of Baraboo.  Constructed during the Late Woodland period, the mound is the only surviving anthropomorphic effigy mound in North America.  The mound depicts a horned humanoid figure and may have held religious or ceremonial significance to its builders.  The mound was preserved as a county park in 1908, listed on the National Register of Historic Places in 1978 and designated a National Historic Landmark in 2016.

William F Romain: William Francis Romain (born 1948) is an American archaeologist, archaeoastronomer, and author.  William Romain received his Ph.D. in archaeology from the University of Leicester and M.A. degree in anthropology from Kent State University.  He is Director of The Ancient Earthworks Project.  He specializes in the study of ancient religions, cognitive archaeology, and archaeoastronomy.  William Romain pioneered the use of LIDAR technology for the analyses of ancient earthworks - most notably those of the Eastern Woodlands.  In 2011 Romain led a team of archaeologists (collectively known as The Serpent Mound Project) in an investigation of Serpent Mound, in Adams County, Ohio.  This was the first major investigation of the effigy in more than one hundred years and included Geoprobe coring, hand coring, limited excavation, ground-penetrating radar, and electric resistivity analysis.  Among the results were new radiocarbon dates for the effigy suggesting it was built about 2,300 years ago by people of the Early Woodland period.  Romain is a past advisor to the Board of Trustees for the Heartland Earthworks Conservancy, former research associate with the Newark Earthworks Center at Ohio State University and past recipient of the Archaeological Society of Ohio's Robert Converse award for Outstanding Contributions to Ohio Archaeology.

Serpent Mound: The Great Serpent Mound is a 1348 ft -long, three-foot-high prehistoric effigy mound on a plateau of the Serpent Mound crater along Ohio Brush Creek in Adams County, Ohio.  Maintained within a park by the Ohio History Connection, it has been designated a National Historic Landmark by the United States Department of Interior.  The Serpent Mound of Ohio was first reported from surveys by Ephraim Squire and Edwin Davis in their historic volume "Ancient Monuments of the Mississippi Valley", published in 1848 by the newly founded Smithsonian Museum.

Alligator Effigy Mound: The Alligator Effigy Mound is an effigy mound in Granville, Ohio, United States.  The mound is believed to have been built between AD 800 and 1200 by people of the Fort Ancient culture.  The mound was likely a ceremonial site, as it was not used for burials.

Lizard Mound County Park: Lizard Mound County Park is a county-operated park in Washington County, Wisconsin near the city of West Bend.  Established in 1950, it was acquired by Washington County from the state of Wisconsin in 1986.  It contains a significant well-preserved effigy mound group.

Supporting paragraphs: William F Romain Serpent Mound
Answer: 1348 ft