The district of the Trasos-Montes, north of the Douro, about the Tamega, Tua and Sabor, was so rugged that Wellington was convinced that Joseph would expect him to advance by the south of the river.
It breaks up into long spurs southwards, deep amongst which are hidden the valleys of Kafiristan, almost isolated from each other by the rugged and snow-capped altitudes which divide them.
On the foothills and in the less rugged mountain districts there is a thin but rich clay soil derived from coral limestone.
The cones, produced in great abundance, are short and oval in shape, the scales with rugged indented edges; they are deep purple when young, but become brown as they ripen.
Between the Russian Pamirs and Chinese Turkestan the rugged line of the Sarikol range intervenes, the actual dividing line being still indefinite.
There are a few plains, like that of David, in Chiriqui province, but irregular surface is normal; and this irregularity is the result of very heavy rains with a consequent extremely developed drainage system cutting river valleys down nearly to the sea-level, and of marine erosion, as may be seen by the bold and rugged islands, notably those in the Gulf of Panama.
It took concentration to maneuver the ever more rugged roads as they climbed skyward, waving away the dust from the other vehicles.
Many of the spurs or broken segments of ranges thus formed abut steeply upon the Black Sea, so that this littoral region is on the whole very rugged and not readily accessible, especially as the general elevations are considerable.
The rusa, or Javan sambar, C. (R.) hippelaphus, is a lighter-coloured and smaller deer than the Indian sambar, with longer, slenderer and less rugged antlers.
But the greater part of this country is a mass of rugged hills cut deep with narrow gorges, within which even the biggest rivers are confined.