The dividing ridge hugs close to the Atlantic, and the rivers, of which there are a great many on this side, plunge abruptly to the sea. On the Pacific side the rivers have a much longer distance to flow before reaching the sea, and the territory bordering on the ocean is low and swampy. The tidal limit of the Tuyra River is nearly fifty miles from its mouth, and on this river and many of its tributaries one can travel many miles inland before ground sufficiently solid to land upon can be found. The vegetation within this low lying area is thick and closely matted together, and this fact taken in connection with the swampy character of the ground, makes travel on foot through any portion of it exceedingly difficult. Therefore the various rivers, which form a very complex system and penetrate everywhere are the natural highways of the country. The chief rivers on the Pacific side are the Tuyra and Boyano with their numerous tributaries and on the Atlantic watershed is the Atrato. A peculiarity noticed at Real de St. Marie, which is at the junction of the Pyrrhi and Tuyra rivers and at which point the tide has a rise and fall of twelve or fifteen feet, was that at low tide it was impossible to enter the mouth of the Pyrrhi with a boat, while five or six miles up the stream there was always a good supply of flowing water and at double that distance it became a mountain torrent. Outside of the swampy area the character of the country is rough and mountainous. The valleys are narrow and the ridges exceedingly sharp, the natural result of a great rain fall. The hills are able to resist the continued wasting effect of the vast volumes of descending water only by their thick mantle of accumulated vegetation, and were it not for this protection the many months of continuous annual rain would long ago have produced a leveling effect that would have made unnecessary the various attempts of man to pierce the Isthmian mountains and form an artificial strait. The ridges are sometimes level for a short distance, but are generally broken and are made up of a succession of well rounded peaks. These peaks are always completely covered with trees and from the top of the sharpest of them it is impossible to get a view of the surrounding country. The highest point climbed was about 2,000 feet above sea level and the highest peak in Darien is Mt. Pyrrhi which is between three and four thousand.