The Miami and Erie Canal required a system to raise boats as much as 513 feet above the Ohio River and lower them from 395 feet above Lake Erie along its 250-mile route through western Ohio. To move boats over the canal’s many hills and obstacles, including villages and dense woods, workers built 105 canal locks. Each lock chamber measured ninety feet long and fifteen feet wide to fit narrowboats that ranged from forty to seventy two feet long and fourteen feet wide. These boats traveled the canal from sunrise to sunset, pulled by donkeys and horses, and took about ten to twenty minutes to pass through a single lock. A lock needed 100,000 gallons of water to help a boat ascend or descend, and boats could travel only up to four miles per hour because greater speed would erode the canal’s clay sides. In northwest Ohio, most locks were built of timber because of the dense Black Swamp, and the wood absorbed water to form a watertight seal. Limestone was used where it was readily available because it did not require the repairs that timber might need if it cracked or leaked. The canal and its locks were built entirely by manpower with simple machines such as inclines and hammers, while horses moved stones and dirt. The stones displayed here were salvaged from Lock Thirty on the Miami and Erie Canal, which stood four miles north of Ottoville just west of Road 25M, and Monterey Township alone had five locks when the canal was established.