Sweeping down from the plateau upon which Curitiba lies, the dramatic mountain range known as the Serra do Mar has long been a formidable barrier separating the coast of Paraná from the interior. Until 1885 only a narrow cobblestone road connected Curitiba to the coast and Paranaguá Bay, and it took two days for mules and carts to cover the 75km from what was, at the time, the main port, Antonina. In 1880, work began on the construction of a rail line between Curitiba and Paranaguá, a port capable of taking much larger vessels than Antonina could. Completed in 1885, this remains a marvel of late nineteenth-century engineering and the source of much local pride, as it is one of the country’s few significant rail lines developed with Brazilian finance and technology. Sufferers of vertigo be warned: the line grips narrow mountain ridges, traverses 67 bridges and viaducts and passes through fourteen tunnels as the trains gradually wind their way down to sea level (see Paranaguá Bay). Passing through the Parque Estadual de Marumbi on a clear day the views are absolutely spectacular, and the towering Paraná pines at the higher altitudes and the subtropical foliage at lower levels are unforgettable. The charming colonial town of Morretes, near the foot of the mountain range, is a good base for exploring the surrounding area.