From Seneca to Aurelius Spain was the economic mainstay of the Empire. Having enriched Tyre and then Carthage, Spanish minerals now enriched Rome; Spain became to Italy what Mexico and Peru would be to Spain. Gold, silver, copper, tin, iron, lead were mined with modern thoroughness; at Rio Tinto one may still see Roman shafts sunk to great depths through solid quartz, and Roman slag with an astonishingly low percentage of copper left in it. In these mines slaves and prisoners worked day after day, in many cases never seeing the light of the sun for months. Great metallurgical industries rose near the mines. Meanwhile the soil of Spain, despite mountains and arid wastes, produced esparto grass for cord, rope, baskets, bedding, and sandals, nourished prize sheep and a renowned woolen industry, and gave to the Empire the best olives, oil, and wine that antiquity knew. The Guadalquivir, the Tagus, the Ebro, and lesser streams helped a web of Roman roads to carry the products of Spain to her ports and innumerable towns.
Indeed, the most remarkable and characteristic result of Roman rule, here as elsewhere, was the multiplication or expansion of cities. In the province of Baetica (Andalusia) were Carteia (Algeciras), Munda, Malaca, Italica (birthplace of Trajan and Hadrian), Corduba, Hispalis (Seville), and Gades (Cadiz). Corduba, founded 152 B.C. was a literary center famous for its schools of rhetoric; here were born Lucan, the Senecas, and Saint Paul’s Gallio; this tradition of scholarship would last through the Dark Ages and make Cordova the most learned city in Europe. Gades was the most populous of Spanish towns, and notoriously rich; situated at the mouth of the Guadalquivir, it commanded the Atlantic trade with western Africa, Spain, Gaul, and Britain. Its sensuous dancing girls ( puellae Gaditanae ) contributed modestly to its fame.
Rome knew Portugal as the province of Lusitania, and Lisbon as Olisipo. At Norba Caesarina, to which the Arabs gave its present name of Alcantara (The Bridge), Trajan’s engineers threw across the Tagus the most perfect of existing Roman bridges; its majestic arches, 100 feet wide and 180 above the stream, still carry a busy four-lane road. The capital of Lusitania was Emerita (Merida), which boasted many temples, three aqueducts, a circus, a theater, a naumachia, and a bridge 2500 feet long.
Farther east, in the province of Tarraconensis, Segovia still enjoys the pure water brought in by an aqueduct built in Trajan’s reign. South of it was Toletum (Toledo), known in Roman times for its ironworks. On the eastern coast rose the great city of Nova Carthago (Cartagena), rich with mining, fisheries, and trade. Out in the Mediterranean lay the Baleares, where Palma and Pollentia were already old and flourishing cities. Northward on the coast were Valentia, Tarraco (Tarragona), Barcino (Barcelona), and, just below the Pyrenees, the old Greek town of Emporiae. A short sail around the eastern end of the mountains, and the traveler found himself in Gaul.
In those days, when all ships were of moderate draught, even ocean-going vessels could navigate the Rhone from Marseilles to Lyons; smaller boats could continue to within thirty miles of the upper Rhine; after a short haul over level land goods could sail by a hundred cities and a thousand villas into the North Sea. Similar overland leaps led from the Rhone and the Saone to the Loire and the Atlantic, from the Aude to the Garonne and Bordeaux, from the Saone to the Seine and the English Channel. Trade followed these waterways and created cities at their meeting points. France, like Egypt, was the gift of her streams.