There exists an invisible line between the Seelie lands and the Unseelie lands called the Silver Veil, and it lets fae know when they're crossing over into enemy territory. Within the veil there is a Market place, known as the Goblin Market, where the two Courts exchange goods (more notably less desirable offspring). Violence is abhorred within the Veil, and any seeking to break the balance in the Veil is trapped by magic, pushing them into the Carcerei: the area of land within the realm where those who have been deemed unworthy are sent. The land itself is barren and being sent there is a dire existence and often a short one for any creature who requires any form of sustenance to survive.
The Silver Veil is protected by the Crow, those charged with the very important job of keeping those from Carcerei where they are and prevent wrong doing within the neutral veil as well as protecting the neutral gates. The Crow are, by reputation, known to be some of the fiercest warriors of fae kind. They all are given a magical cloak) that allows them to turn into crows. It gives them the ability to cloak themselves from would-be passers by and keep the entrance of the gates hidden from outsiders.
The land itself in the Veil is covered by a thin, silvery layer of fog. It is gorgeous, fertile land and those who are fortunate enough to live on it (mainly merchants and guards), often live prosperously with the bounty of the land. Due to it's neutral central location and beautiful scenery, it is the only place the two Kingdom Royalty (the Unseelie and the Seelie) will ever meet, and usually in matters that will effect all of the fae world or in dealing with problems with Carcerei. There is no palace for these meetings. Rather the two meet in nature, and humble themselves to the raw magic of the land.