Titus Livius (Livy), The History of Rome, Book 34
Evan T. Sage, Ph.D. Professor of Latin and Head of the Department of Classics in the University of Pittsburgh, Ed.

9. Even at that time Emporiae consisted of two towns separated by a wall. One was inhabited by Greeks from Phocaea, whence came the Massilienses also, the other by the Spaniards; [2] but the Greek town, being entirely open to the sea, had only a small extent of wall, of less than four hundred paces in length, while the Spaniards, who were farther back from the sea, had a wall three miles around. [3] A third class of inhabitants, Roman colonists, was added by the deified Caesar¹ after the final defeat of the sons of Pompey, and at present all are fused into one mass, the Spaniards first, and later the Greeks, having been received into Roman citizenship. [4] One who saw them at that time would wonder what secured the safety of the Greeks, with the open sea on one side and the Spaniards, so fierce and warlike a people, their neighbours on the other. Discipline was their protector against their weakness, [p. 443]which among more vigorous peoples is best main² tained when there is cause for fear.³ [5] The part of the wall which faced the interior they kept strongly fortified, with only a single gate leading in that direction, and at this one of the magistrates was posted as a continuous guard. [6] At night a third of the citizens kept vigil on the walls; they did this not merely as a result of custom or in obedience to the law, but they posted their sentinels and sent out their patrols with all the care they would have used had the enemy been at their gates. [7] No Spaniard was admitted to the city, nor did the Greeks themselves leave the city without good cause. Towards the sea the gates were open to all. [8] Through the gate which led to the Spanish town they never passed except in large bodies, usually the third which had maintained the watch on the walls the night before. [9] The cause of going out of the town was this: the Spaniards, who had no experience with the sea, enjoyed transacting business with them, and wanted both to buy the foreign merchandise which they brought in in their ships and to dispose of the products of their farms. The desire for the benefits of this interchange caused the Spanish city to be open to the Greeks. [10] They were safer, too, for the reason that they were under the shelter of the Roman friendship, which they cultivated with resources inferior to those of the Massilienses but with equal devotion. At this time also they received the consul and his army with courtesy and kindness. [11] Cato delayed there a few days, until he could find out where the forces of the enemy lay and what strength they possessed, and, not to be idle even in that time of waiting, he spent the whole period in drilling his [p. 445]troops. [12] It happened to be the time of year when⁴ the Spaniards had the grain on their threshing floors; he therefore forbade the contractors to purchase any and sent them back to Rome, saying, “This war will support itself.” [13] Leaving Emporiae, he burned and laid waste the fields of the enemy and filled everything with flight and terror.