Chartered in 1825, the Louisville and Portland Canal Company was authorized to construct a canal around the rapids called the "Falls of the Ohio." Construction started on March 1, 1826. The canal and first generation of locks were completed in 1830. As originally constructed, the canal was 1.9 miles long, 64 feet wide, and terminated at its lower end with a three-flight lock system with a total lift of 26 feet. Each lock chamber was 198 feet long between miter posts, with available length for vessels of 183 feet, width of 52 feet, and a lift at low stages of 8.5 feet.
The Portland Head Light was the first lighthouse to be constructed in Maine and the first one completed and put into service by the Federal government under the Lighthouse Act of 1789, which moved to place all lighthouses under federal control. While work had begun on the lighthouse in 1787 by the State of Massachusetts which, at that time, had jurisdiction over Maine, it was completed by the Federal government. When this lighthouse was being built, Portland was the sixth largest port in the country, the closest port to Europe and had significant trade with the Caribbean.
The Portland Observatory was built in 1807 by Captain Lemuel Moody to serve as a communication station for Portland Harbor. Portland Observatory was one of the earliest marine signal stations in the United States, and it is the last known to survive. The Observatory's location on Munjoy Hill gave it a clear view of vessels approaching Portland Harbor. The Observatory contributed to the prosperity of Portland Harbor as a vital center of maritime commerce during the "Golden Age of Sail."