The manmade waterway that connects the Atlantic and the Pacific oceans is the Panama Canal.
panama canal
Man made
A manmade feature, such as a building or road, can provide shelter, transportation, or facilitate communication. Terrain features, such as mountains or rivers, can provide natural resources, serve as barriers for defense, or offer opportunities for recreation.
The Panama Canal
the Panama Canal is a manmade pathway through the country Panama in Central America that is a shortcut to the Atlantic Ocean from the Pacific and vise versa. It was originally created for naval purposes but has since been used for cargo and travel.
The St. Lawrence river is 100% natural.
Its locks
The Panama Deception won the Oscar for Documentary - Feature - in 1992.
Ireland's manmade features are Newgrange Carrowmore Megalithic Cemetery, Round Towers, and High crosses. Leviathan and Simon and Goliath. The book of Kells is also a manmade feature.
The Panama Canal.
The Isthmus Of Panama