The opposite end of the harbor was the city of Manila proper. The Spaniards had taken a small peninsula framed on one side by the Bay and on two others by rivers: the Pasig, and a welter of pissant tributaries that joined the Pasig just short of where it emptied into the Bay. They had enclosed this peninsula in a modern sort of slope-sided wall, a couple of miles in circuit, and erected noble bulwarks and demilunes at its corners, rendering it impregnable to land assault by Dutch, Chinese, or native legions. The outlet of the Pasig was dominated by a considerable fortress whose guns commanded the river, the Bay, and certain troublesome ethnic barangays across the river.