Portals are a powerful mode of transport among the magically capable empires and people that have existed on Toril throughout its history. A portal is cheaper than a Gate, easier to create, relatively reliable, and more or less permanent within the lifetime of the creator or the empire that commissioned it, as a result Toril is littered with thousands of portals linked together in networks that allow people to travel great distances in the blink of an eye.
Portal Networks are usually created for some great need (to transport an army or group vast distances) or as a memorial to mark significant places or events in history.
The Trail of Merrshaulk’s Scales: This portal network tracks the migratory movements of the sarrukh clans outcast from Okoth as they wandered Faerun to establish the lands of Mhairshaulk and Isstosseffifil. Portals along this network are known to exist in their sacred homeland around the Lake of Steam, along the shores of the Vilhon Reach, the jungles of Chult, deep in the forests of the Western Heartlands, and lastly in the once lush lands of Anauroch.
The Trail of Serpent’s Tears: This portal network looks like a coiled snake when the portals are plotted on a map of Faerun. The portal network is believed to have been created by Keoth Amsetis, otherwise known as the godking Set of Mulhorand. Those who follow the path laid out by Set millennia will supposedly find parts of the fabled Book of the Serpent (Set’s own spellbook and diary) and learn the secrets to attaining godhood.