Question: What is the highest point of the state governing Langdon House?

full_context: Document 1: Langdon House: The Langdon House is a historic house on the eastern side of Cincinnati, Ohio, United States. Located along Eastern Avenue, it is a frame house with weatherboarded walls, built in the Steamboat Gothic style. It was erected in 1855 in the village of Columbia, which has since been annexed to the city of Cincinnati. Seven years after it was constructed, its owner, Henry Langdon, joined the 79th Ohio Infantry to fight in the Civil War. After his return in 1865, Langdon returned to his Columbia house; there he maintained a medical practice until his 1876 death.
Document 2: Boston: Boston has an area of 89.6 square miles (232.1 km2)—48.4 square miles (125.4 km2) (54.0%) of land and 41.2 square miles (106.7 km2) (46.0%) of water. The city's official elevation, as measured at Logan International Airport, is 19 ft (5.8 m) above sea level. The highest point in Boston is Bellevue Hill at 330 feet (100 m) above sea level, and the lowest point is at sea level. Situated onshore of the Atlantic Ocean, Boston is the only state capital in the contiguous United States with an oceanic coastline.
Document 3: Whitby Mansion: The Whitby Mansion is a historic mansion in Sidney, Ohio, United States. Built in 1890, it was originally the home of W.H.C. Goode, a Sidney industrialist. Descended from one of the First Families of Virginia, Goode first purchased property in the vicinity of Sidney in 1849. Having gained complete ownership of the leading steel scraper manufacturing company in the United States in 1877, Goode began to build his mansion on Sidney's northern side in the late 1880s. The resulting mansion, designed by an unknown architect, features massive stone walls that are topped with a slate roof. Elements of the Jacobethan and Châteauesque styles are combined with the Tudor Revival style of architecture. By the mid-1970s, the mansion had ceased to be a house; it had been purchased by The Way International and converted into a historic archive and art museum. Today, the property is owned by GreatStone Castle Resorts, which operates it as a bed and breakfast.
Document 4: Charles Kent House: The Charles Kent House, also known as the Palmer House, is a historic structure in Kent, Ohio, United States. It has been listed on the National Register of Historic Places since February 23, 1978. An example of Gothic Revival architecture, the house also features elements of the Greek Revival and Carpenter Gothic architectural styles. It is at 125 North Pearl Street in central Kent, immediately north of the West Main Street District. It was built in 1843 as the home of Charles Kent, son of Zenas Kent and brother of Marvin Kent, the namesake of the city of Kent. In 1909 it was moved by owner Henry Green north of its original location along West Main Street to the site on North Pearl Street. Martin L. Davey, who would later serve as mayor of Kent, followed by U.S. Representative, and eventually as Governor of Ohio, persuaded the owner to move the house to avoid demolition.
Document 5: Doan House: The Doan House is a historic residence in the city of Wilmington, Ohio, United States. Constructed in the middle of the nineteenth century for a local medical official, it was for many years the home of one of the city's prominent lawyers. The house's prominent location at the city's edge and its distinctive architecture have made it a local landmark, and it has been designated a historic site.
Document 6: Columbus Pump House: The Columbus Pump House, which is also known as the Columbus Power House, and the Senior Center, was designed by architect Harrison Albright and completed in 1903. In 2016 the building was renovated to become a restaurant for the Upland Brewing Company. The building stands on the banks of the East Fork of the White River at the foot of Second Street in Columbus, IN, Indiana. From 1903 to 1951 it served as the city's water works and pumped water from the river for domestic use; it also produced electricity for the city's street lighting. The city sold the property in 1952 and it was renovated to become Southern Machine Company. With a 1976 renovation it became the home to the "Senior Center", which used the building until 2011 when that group relocated into the newly built Mill Race Center. It is currently a brewpub operated by Upland Brewing Company.
Document 7: Portland, Oregon: Though much of downtown Portland is relatively flat, the foothills of the Tualatin Mountains, more commonly referred to locally as the ``West Hills '', pierce through the northwest and southwest reaches of the city. Council Crest Park, commonly thought of as the highest point within city limits, is in the West Hills and rises to an elevation of 1,073 feet (327 m) The city's actual high point is a little - known and infrequently accessed point (1,180 feet) near Forest Park. The highest point east of the river is Mt. Tabor, an extinct volcanic cinder cone, which rises to 636 feet (194 m). Nearby Powell Butte and Rocky Butte rise to 614 feet (187 m) and 612 feet (187 m), respectively. To the west of the Tualatin Mountains lies the Oregon Coast Range, and to the east lies the actively volcanic Cascade Range. On clear days, Mt. Hood and Mt. St. Helens dominate the horizon, while Mt. Adams and Mt. Rainier can also be seen in the distance.
Document 8: Madison Historic District (Madison, Indiana): Many of the prominent buildings in the district were built by Madison-native-architect Francis Costigan, who favored the Greek Revival style. Two of these are National Historic Landmarks: the Lanier Mansion, and the Charles L. Shrewsbury House. The Lanier Mansion was the former home of James Lanier, who lent money to governor Oliver P. Morton to run the Indiana state government to circumvent the legislative process between 1862-1865. The Shrewsbury-Windle House was built for steamboat captain Charles Shrewsbury, who would later become a mayor of Madison. Costigan, himself, built his home in the district, and it is considered one of the best uses of a narrow lot by modern architects. A thirty-foot parlor is considered the highlight of the House.
Document 9: Campbell Hill (Ohio): Campbell Hill is, at 1,550 feet (470 m), the highest point in elevation in the U.S. state of Ohio. Campbell Hill is located within the city of Bellefontaine, 2 miles (3.2 km) northeast of downtown.
Document 10: Tennessee: The highest point in the state is Clingmans Dome at 6,643 feet (2,025 m). Clingmans Dome, which lies on Tennessee's eastern border, is the highest point on the Appalachian Trail, and is the third highest peak in the United States east of the Mississippi River. The state line between Tennessee and North Carolina crosses the summit. The state's lowest point is the Mississippi River at the Mississippi state line (the lowest point in Memphis, nearby, is at 195 ft (59 m)). The geographical center of the state is located in Murfreesboro.
Document 11: Joseph C. Hays House: The Joseph C. Hays House at 103-105 West Main Street in Sharpsburg, Maryland, United States was originally built in 1823 as a three-bay side hall double-parlor house in the Federal style. It was soon expanded to the east with a two-bay parlor and one commercial bay. The east parlor entered commercial use during the mid-19th century as a dry goods store operated by Benjamin F. Cronise. "Circa" 1920 a storefront was added and a copper front was applied with BANK lettered under a central pediment, behind a marquee.
Document 12: Oklahoma: Oklahoma has four primary mountain ranges: the Ouachita Mountains, the Arbuckle Mountains, the Wichita Mountains, and the Ozark Mountains. Contained within the U.S. Interior Highlands region, the Ozark and Ouachita Mountains mark the only major mountainous region between the Rocky Mountains and the Appalachians. A portion of the Flint Hills stretches into north-central Oklahoma, and near the state's eastern border, Cavanal Hill is regarded by the Oklahoma Tourism & Recreation Department as the world's tallest hill; at 1,999 feet (609 m), it fails their definition of a mountain by one foot.
Document 13: Seattle: The city itself is hilly, though not uniformly so. Like Rome, the city is said to lie on seven hills; the lists vary, but typically include Capitol Hill, First Hill, West Seattle, Beacon Hill, Queen Anne, Magnolia, and the former Denny Hill. The Wallingford, Mount Baker, and Crown Hill neighborhoods are technically located on hills as well. Many of the hilliest areas are near the city center, with Capitol Hill, First Hill, and Beacon Hill collectively constituting something of a ridge along an isthmus between Elliott Bay and Lake Washington. The break in the ridge between First Hill and Beacon Hill is man-made, the result of two of the many regrading projects that reshaped the topography of the city center. The topography of the city center was also changed by the construction of a seawall and the artificial Harbor Island (completed 1909) at the mouth of the city's industrial Duwamish Waterway, the terminus of the Green River. The highest point within city limits is at High Point in West Seattle, which is roughly located near 35th Ave SW and SW Myrtle St. Other notable hills include Crown Hill, View Ridge/Wedgwood/Bryant, Maple Leaf, Phinney Ridge, Mt. Baker Ridge and Highlands/Carkeek/Bitterlake.
Document 14: Joseph A. Hemann House: The Joseph A. Hemann House in Cincinnati, Ohio, was built in 1870 by Joseph A. Hemann (1816-1897) and served as his residence for about ten years. It is located in Hamilton County in the neighborhood of Clifton on the corner of West McMillan and Hollister. Mr. Hemann was the founder of the Cincinnati Volksfreund in 1850.
Document 15: Cheaha Mountain: Cheaha Mountain / ˈtʃiːhɔː /, often called Mount Cheaha, is the highest natural point in the U.S. state of Alabama. It is located a few miles northwest of the town of Delta in Cheaha State Park, which offers a lodge, a restaurant, and other amenities.
ground_truth: Campbell Hill
sub_queries: Which state is Langdon House located? Answer: Ohio
what is the highest point in the state of Ohio Answer: Campbell Hill