Excepting Aspinwall, which is a cosmopolitan place, the city of Barranquilla is the principal port of Colombia, and to it all merchandise and passengers bound for Bogota and the interior of the country must go. In the old Spanish colony times Carthagena was the greatest commercial metropolis of Colombia, or New Granada, as it was then called; and it is one of the quaintest, as it is one of the oldest, cities in South America. In the time of Philip the Second it was the most strongly fortified place on the continent, and the headquarters of the Spanish naval forces in the New World. It was the rendezvous of the Spanish galleons which came to South America for treasure. There are many rich mines in the mountains back of the city, which have produced millions in silver and gold. Here came the pirates to plunder. They committed so much damage that the King of Spain thought it worth his while to build a wall around the entire city, on the top of which forty horses can walk abreast, and which is said to have cost ninety million dollars. [Illustration: BARRANQUILLA.] Carthagena was the seat of the Inquisition, and in Charles Kingsley’s novel, “Westward Ho!” its readers will find a charming description of the place. It was here that Frank and the Rose of Devon were imprisoned by the priests, and the old Inquisition building in which they were tortured and burned is still standing. But it is no longer used for the confinement and crucifixion of heretics. For nearly sixty years after the overthrow of the Catholic Church it stood empty, but it is now occupied as a tobacco factory. There is an underground passage between the old Inquisition building and an ancient fortress upon a hill overlooking Carthagena, through which prisoners used to be conducted, and communication maintained in time of siege; but, like everything else about the place, it has long been in a state of decay. Some years ago a party of American naval officers attempted to explore the passage, but found it filled with obstructions, and were compelled to abandon the enterprise. The old castle is obsolete now, and in a state of ruin, being used only as a signal station. When a vessel enters the harbor a flag is run up by a man on guard to notify the Captain of the Port and the merchants of its arrival. [Illustration: CARTHAGENA.]