A ley-line is a powerful flow of magical energy, invisible to everyone except those who have the Mage-Gift. Ley-lines are formed and flow like rivers, and may cross with other ley-lines, resulting in a Node. Ley-lines are natural phenomenon, but can also be artificially created by very powerful mages. It requires a Master rank mage to tap into a ley-line, as any mage below Master rank would simply be overwhelmed by the sheer power contained in a ley-line.
Positions of Ley-Lines
Ley-lines are located throughout all of Velgarth, seemingly randomly. However, ley-lines are actually created by the flow of life-energy. Wherever things live, their energy will pool together and flow down through the world and create the ley-lines.
After the Mage Storms, the magical energy in Velgarth has been dispersed evenly. While it is uncertain if this phenomenon caused the ley-lines to disappear for a period of time, the general consensus is that there is now not enough energy currently running in the ley-lines to attempt any of the major workings of magic, such as Gating, that were possible prior to the disruption of the Mage Storms. The energy in the ley-lines is not expected to return to their pre-Mage Storms levels for decades, if not centuries. Some mages also suspect that there have been some movement in the placement of ley-lines because of this.
Certain ley-lines are manually moved by Master- and Adept-level mages, so they can keep their power closer to their lairs. Most ley-lines, unless kept through spells keyed by Adepts, will flow back to their natural course, much like attempting to divert a river.
After the disruption caused by the Mage Storms, Tayledras Masters and Adepts have been going out to map out and reestablish disrupted ley-lines and nodes. The Tayledras do this in order to not only heal and reverse damage caused by the Mage Storms and the Changecircles, but also to prevent other unscrupulous mages from hoarding the power of the Nodes. While the Tayledras may key the reestablished nodes to themselves or to certain allies, they also establish a flow of magical energy for all mages to use --- something that a power-hungry mage may not do, choosing instead to "dam" all the power for himself.
Accessing a Ley-Line
Due to the massive amounts of power present in a ley-line, only very powerful Mages are able to access them. No mage below the rank of Master-level is capable of tapping into their power. Even the smallest of ley-lines are filled with too much power for the lesser mages to use. Some mages are able to access smaller flows, similar to little streams, of magical energy that feed into ley-lines. The ability to tap into a ley-line is determined by a mage's power and discipline. A sufficiently powerful mage may tap into a ley-line, but if that mage is not trained or disciplined enough, the power of the ley-line may overwhelm him to the point that any magical ability he has will be burnt out.
Upon tapping into a ley-line, it is imperative that a mage (and any shields the mage employs) must be Grounded, else the power may overflow explosively. The accessing of ley-lines is known to create heat, though it can be lessened with proper shielding. This heat was used by Darian to dry his friends.
A Mage constantly working with ley-lines and nodes gradually develops shock-white hair. Among the Tayledras, this curious side effect is one of the hallmarks of an Adept. It has also been mentioned that the white color of Companions is due to their natural ability to tap into nodes and ley-lines to augment their physical abilities, such as their endurance.