Fog will form if the air temperature drops below the dew point, which is the capacity of the air to hold moisture in suspension. If the temperature drop far enough the moisture content will exceed saturation point, causing it to form visible water vapour.
It happens in the early mornings or late after noons.
The largest man made canal in the world is The Suez Canal. It is a sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez.
It was constructed by the Suez Canal Company between 1859 and 1869.