At the foot of the house of Columbus is part of the old city wall erected in 1537 and of which numerous portions remain intact, though all traces of the moat have disappeared. The old city was in the form of a trapezium occupying an area of a caballeria or about 200 acres, and the wall on the north side, provided with numerous redoubts and watch towers, was much the longest, the western wall being the shortest. Santo Domingo is one of the cities of the Spanish main which lay claim to the story that when the accounts for the city's walls were laid before the king of Spain, he went, to the window and gazed at the horizon, saying he was "looking for the reflection of those walls, for they must be built of gold, they cost so much." Judging by the relative size of the walls, the story should rather be awarded to Cartagena, in Colombia, or possibly to another city, but Santo Domingo's walls are massive enough to have justified the Spanish king in squinting at the horizon, at least. The ancient gates which were formerly closed from sunset to sunrise, still remain, but no longer afford the only means of ingress and egress as breaches have been made in the walls at most street terminations. The most famous of the old gates is the "Puerta del Conde," "Gate of the Count," so called because it was constructed by the Count of Penalva, Governor of Santo Domingo, about 1655, though the bastion through which it leads is as old as the city wall. It was here that the cry of independence was raised on February 27, 1844, and it is therefore regarded as the cradle of Dominican independence and its official name is "Bulwark of the twenty-seventh of February." Another important gate is the "Gate of San Diego," also called "Gate of the Admiral," near the ruins of Diego Columbus' house and affording communication with the wharves on the Ozama River. It is one of the original three gates of the city. Up the river, near the lumber market, is a very old ceiba tree to which it is claimed Columbus once tied up his vessel. Still further up the river is a spring the enclosure about which is said to have been built by Diego Columbus.