Finely detailed map of a portion of Panama, prepared to illustrate John Augustus Lloyd's article Account of Levellings Carried Across the Isthmus of Panama, presented at the Royal Geographical Society in 1830.

This detailed topographical map depicts the region surrounding the narrowest portion of the Isthmus of Panama, based on surveys conducted by John Augustus Lloyd between 1828 and 1829. Around the time that railroads were being invented, President Bolivar of Gran Colombia commissioned a study of the area between Chagres and Panama City with the intent of building a railroad to connect the Atlantic to the Pacific Ocean. Although the report concluded that a railroad was possible, the project was abandoned until 1850, when US privateers began building the Panama Railroad.

This map depicts two potential rail road lines to the Pacific, both extending from the River Trinidad: the nearest line and a proposed line. A large inset shows a bird's-eye plan of Panama City.