2and partly at the request of the people, and partly at the instance of Scipio, he undertook to watch over the city, that it might not, either willingly or unwillingly, attach itself to Caesar. For the place was in every way advantageous for those who held it, and fully capable of defence; and it was still further strengthened by Cato. For he brought in a great abundance of grain, and perfected the walls by building towers and by running formidable trenches and palisades in front of the city.