Strabo Geography 3.4.16

[16] Iberia produces a large quantity of roots used in dyeing. In olives, vines, figs, and every kind of similar fruit-trees, the Iberian coast next the Mediterranean abounds, they are likewise plentiful beyond. Of the coasts next the ocean, that towards the north is destitute of them, on account of the cold, and the remaining portion generally on account of the apathy of the men, and because they do not lead a civilized life, but pass their days in poverty, only acting on the animal impulse, and living most corruptly. They do not attend to ease or luxury, unless any one considers it can add to the happiness of their lives to wash themselves and their wives in stale urine kept in tanks, and to rinse their teeth with it, which they say is the custom both with the Cantabrians and their neighbours. ¹ This practice, as well as that of sleeping on the ground, is common both among the Iberians and Kelts. Some say that the Gallicians are atheists, but that the Keltiberians, and their neighbours to the north, [sacrifice] to a nameless god, every full moon, at night, before their doors, the whole family passing the night in dancing and festival. The Vettones, the first time they came to a Roman camp, and saw certain of the officers walking up and down the roads for the mere pleasure of walking, supposed that they were mad, and offered to show them the way to their tents. For they thought, when not fighting, one should remain quietly seated at ease. ²