Planning for a base.

[Harry Dresden]

Is there an upper limit on the size of a base? Harry was a founder of something called the Paranet back home, a group of practitioners of magic that couldn't make full wizard. The principle behind it was strength in numbers, and in the Omniverse, I was thinking he'd be able to take it a step further, providing a place of refuge for a large number of people once he got enough Omnilium to have a base.

My first idea is to use the White Council base at Edinburgh. The base wouldn't be Edinburgh Castle itself, but rather the network of tunnels underneath it, perhaps carved out of a preexisting cave system, or underneath an empty castle in Camelot.

This leads to my second question; could bases have "public" areas? Places where access is assumed to be granted unless banned, divided from places that need access approval or force of arms to enter?