Portals

One of the great gifts of The Pact, portals allow travel between fixed points (other portals) based on a combination of linked coordinate magics, geomancy, and - well, frankly, some people having the gifts to convince some rocks or trees or water to do them a favour.

History

The Portals were originally the work of the Fatae, and it was only the Fatae who could create them. For a long time (up until the 1910s), only the Fatae could create portals that reliably crossed water. There is a longstanding network of portals that crosses continental Europe that were created pre-Pact, and that allow access by portal to Paris, Aachen, Rome, Venice, and other of the various more ancient cities of Europe. On the map below:

Black: Defunct or inaccessible
Purple: Fatae created (before the Pact)
Grey: Stone portal (created since the Pact)
Blue: Water portal (created since the Pact)
Green: Tree portal (created since the Pact)

The earliest portals in Albion are, in order (though several of them are no longer functioning or accessible):

Dinas Emrys: The Council Keep
Schola
Tintagel (no longer accessible)
The Tower of London (no longer accessible)
Dover Castle
Windsor Castle (no longer accessible)
Oxford University
Trellech

Creating and maintaining

As part of the Pact, the Fatae taught a select group how to create and maintain them. Portals since the Pact come in three forms: water, stone, and tree. (Tree portals are the shortest lived, relatively speaking, and will need adjustments or relocation after a few hundred years on average.) Portals are 'grown' more than created, a process that usually takes months to years of regular attention from the portal keeper(s) responsible. Strongly magical locations can make this easier - or they can make it more challenging to anchor the portal correctly. Magical interference in the area the portal draws from can damage, weaken, or even close it. Portals are fussy and complex to maintain (and can be expensive to restore or repair), and so they generally exist in places that can support that upkeep. Trellech has seven public portals in Portal Square, London has three (in Bedford Square, Southwark, and Spitalfields), as well as the Five Schools. Most estates that are linked to the land magic have them, as do other established estates. On general, you can assume that any magical community over 1000 people has one, as do the primary landed estates for the Lords and Ladies of the land. There are of course a number of others, since they're a very convenient and effective status symbol for those who could support building one. Portals may be public or private. If private, the Lord (or whoever is responsible for the local warding) usually is the one to determine access. This can be allowed by token, by alignment to the portal, or by some particular magical password. In some place, there is a fee to reserve a particular time or to get precedence in the line. (And privately held portals can and do set their own fees.)

In practical terms

Portals require highly trained specialists to construct and maintain (maintenance depends on how often they're actually used.) Avigail Levy and Rathna Stone are both Portal Keepers, and portals are discussed at length in The Fossil Door, Three Tales of Gabe and Rathna and Old As The Hills where Rathna takes on an apprentice. It also mentions Davis Fortnum as a Portal Keeper. There is a short recharging period between uses. Busy portals (such as Trellech) schedule in 5 or 10 minute intervals to allow for this, and you may need to make reservations in advance or wait for an opening. (There is also a regular cycle of portals between the most common locations - Trellech, the three London portals, and the Five Schools.) Portal Square in Trellech has waiting rooms and other spaces to make this easier. People with urgent government business or medical emergencies can jump the line - portals in busy locations have attendants who oversee the queue and manage any unusual situations. The portals form a network of communication, with regularly scheduled mail drops that allow mail to move from portal to portal three or four times a day. It also makes it easier to deploy emergency assistance (by the Guard, Healers, Penelopes, or others) as needed for local events, as long as there is a portal available nearby.

The Guild

The Portal Keepers have a long apprenticeship. (Old As The Hills discusses this in some detail). They have a guild hall with office space in Trellech, but for the last century or so have had a country estate with an orangery used to grow the trees for portals up to saplinghood. (Seen in Old As The Hills). That estate also has multiple libraries, work spaces, and offices.