cardo

thumb|Roman cardo in Jerash, JordanA cardo (: cardines) was a north–south street in ancient Roman cities and military camps as an integral component of city planning. The cardo maximus, or most often the cardo, was the main or central north–south-oriented street.

==Etymology== "Cardo" is the Latin word for "hinge". Being the hinge the turning point of the doors, the word cardo would also be used to designate other “turning points”, like the North Pole of the sky, or the four cardinal directions (quattuor cardines orbis terrarum). Also "the principal line laid down in surveying land was called cardo", which is also applied to the first street of a city: the street around which the city would be structured.