Nexus of Magic
Nexus of Magic is the source of all magic on Earth. From it magical energy travels to every living being on the planet.
The Nexus is said to be a place with a high concentration of magical energy. According to myths and legends there is a massive ball of magical energy. Because of that any spell cast in the Nexus would be much stronger than spells cast outside. Some people even say that spells which have to be cast by multiple magic-users could be cast by a single person in the Nexus. The amount of magical energy is also said to interfere with any technology which needs some kind of a wireless signal to function.