The neighbouring fastnesses, famed throughout the world for their strength, Antwerp and Ostend, Ypres, Lisle and Tournay, Mons and Valenciennes, Cambray and Charleroi, Limburg and Luxemburg, had opened their gates to conquerors; but never once had the flag been pulled down from the battlements of Namur.

That nothing might be wanting to the interest of the siege, the two great masters of the art of fortification were opposed to each other.

Vauban had during many years been regarded as the first of engineers; but a formidable rival had lately arisen, Menno, Baron of Cohorn, the ablest officer in the service of the States General.

The defences of Namur had been recently strengthened and repaired under Cohorn's superintendence; and he was now within the walls.

Vauban was in the camp of Lewis.