The Equatorial Mountains, or Montes Aequinoctialis, are a massive range of mountains encircling Darwin IV's equator. It is only broken briefly by the Sinus Columbus, the great pass through the range.
Darwin IV's montane region almost completely encircles the globe along the equator. While not impassable, the mountains present many problems for the planet's huge migratory herds. Storms and fogs claim thousands of individuals each year as they traverse the difficult and often icy mountain passes.
There are foothill regions that border the great equatorial mountain range. The rolling hills gradually give way to a rougher, bleaker landscape in which mists and rain are not uncommon. In contrast to the plains' flatness and monotony, this hilly region offers wonderfully varied vistas, all with a distant backdrop of gray, mist-shrouded crags. Though there are occasional dense pockets of scrub-growth between the hills, the greater portion of ground is covered by hillvine. The hilltops have the heaviest sprinkling of larger rocks, leading to the speculation that these are eroded remains of ancient volcanic plugs.
On the rolling ground, the soil is saturated and very spongy, and in some areas there is a fine, rainbow mist hovering about a meter above the surface, often caused by exhaling peat-bladders.
The Mountains Themselves
The mountains of Darwin IV are relatively young, sharp-edged and jagged, though not terribly high. Very few peaks remain sheathed in snow through the year. Looking all the more forbidding for their bareness, they form a planet-girdling band, evidence of Darwin IV's active subcontinental shield regions.
There are tricky alpine updrafts.
Mountains streams on Darwin IV are not entirely rich in plant life.