The Villa of Bilbao as such was officially born on 15th June 1300, when D. Diego López de Haro bestowed the Carta Magna upon it.
Bilbao, like many others cities in the world, is situated on the banks of a river. This river, the Nervión, supplies drinking water as well water for irrigation and inshore fishing, thus offering food as well as water for its inhabitants. In addition, with the passing of time, the estuary has proved to be best means of communication with the exterior.
At the beginning there were two nuclei of population, two settlements of differing character: that of the left bank, or Old Bilbao , who were miners and iron-workers, and that of the right bank, or Old Town, who handled all the comings and goings of mercantile port traffic. Both parts were united by San Anton Bridge, and here there was a harbour just at the point where the high tide reached furthest inland.