My urban fantasy setting, in which mythical creatures live in secret amongst the human race in the late 90s USA, has a species known as snow elves (my setting's take on Christmas elves) who are capable of creating portals from one location to another, and I'm trying to work out how this secret society would elect to set up their portal transportation networks given these portals' rules and limitations, which are as follows:

By laying their hand on a flat, reasonably-smooth surface, a snow elf can mark that surface as the center point of a portal. They can mark two surfaces at a time, one with their left hand, and one with their right. Once they have marked two surfaces, they can open and close a portal between them at will with a thought, from any distance, at any time, and can make it any diameter between 6 inches and 10 feet, providing the surface is large enough to fit such a circular portal.

The surfaces will remain marked until either the snow elf marks new surfaces, or the witching hour begins (which is at 4:00 AM GMT), which in addition to disrupting portal marks and a great deal of other magical energies, causes time to stop for an hour for anything non-magical.

The main takeaways from this are that 1: you need one snow elf for every connection between two places, 2: either the snow elf or an object they have marked needs to physically get to the location they want to make a portal to, and 3: whatever portal network they set up needs to be re-built from scratch every day.

Beyond that, immortals also have access to human society's methods of transportation (and there are enough immortals who can pass for human that they can use these with little issue).

With these facts in mind, the first thing I'd like to work out is the ideal structure for these portals. How they would arrange the locations of these portals to maximize ease and speed of daily setup, and allow a user of this portal network to get to as many places as possible as conveniently as possible, with as few snow elves needing to be employed as possible.

What would be the ideal framework for this network of portals?

  • $\begingroup$ But why would the snow elves be setting up these portal networks? That would probably drive the complexity and how dense they are. They could just set up 5-6 in the city for major hubs. Probably won't take that much time, even. Or do they try to set up really complex ones like "inside the bank vault" and similar? Also do they try to make hundreds of portals so you can get anywhere? It might not even be a problem if they just take commissions and make, say, 5 portals a day. $\endgroup$
    – VLAZ
    Commented Apr 3, 2023 at 20:27
  • $\begingroup$ @VLAZ The main purpose is to enable swift transportation and communication between distant major hubs of immortal activity. A lot of immortal species can't go out in public due to being visibly non-human, and as a later part of this question will discuss, immortals are extremely sparing and hesitant with phones and email and the like since they don't know when humans will suddenly be secretly spying on these forms of communication, if they aren't already. $\endgroup$ Commented Apr 3, 2023 at 20:32
  • $\begingroup$ I'd probably set up a haulage company where all the truck drivers are snow elves. It's the perfect smokescreen: you can create the portals inside the trucks and nobody would suspect that your drivers follow weird time schedules or that objects arrive in your trucks that weren't there at the start. Sure, you'd need to magic up some paperwork to cover your tracks but this being the 90s, police wouldn't have instant access to centralised cargo databases yet. $\endgroup$
    – biziclop
    Commented Apr 4, 2023 at 13:49
  • $\begingroup$ Once a snow elves established both ends do they need to present to open it for another person? Is it to practical to open a portal and leave it open for hours? If they are at end A of their portal and someone arrives at the B side and wants though how does the person at B use the portal? $\endgroup$ Commented Apr 4, 2023 at 21:39
  • 1
    $\begingroup$ I feel like you're asking us to optimize a transportation network without knowing why or how often people would be using the network, how big an area the network covers, or how large your maintenance workforce is compared to the network. There are many, many other variables, like the list of obstacles along a snowelf's daily path. I don't think that this question is answerable. $\endgroup$ Commented Apr 5, 2023 at 0:57

3 Answers 3


This is a Frame Challenge

So... Assuming nothing changes in the day, every day a fleet of elves need to run around the city and/or country placing portal ends? Unless you intend this network to be really, really limited, that sounds either...

  • (a) exhausting (Frank, place your first portal at 22 Elm Street on the wall behind the trash cans then run like the wind cross town - don't be seen - to place the other at 4432 Lakeside under the viaduct) or,
  • (b) there's so many portals that humans can't help but find them (Frank, you cover block #1, Jimmy, block #2, Kara, block #3...).

And cross-country portals would be almost impossible. How do the elves get people from city to city to city and country to country to country without being detected... every 24 hours?

This doesn't seem practical. Off hand, I can't see a way to create a useful network that is both hidden from the humans and sizeable enough to matter. After all, it collapses every 24 hours. Unless you have elves that can hide while flying commercial jet liners, they're only setting up small, in-city networks. Like I said, sounds impractical.

Consider modifying your rules so that the network collapses, but the assignment of portal locations is not lost. There's a cost in magic every morning to re-establish the network (the elders gather together and sacrifice a goat or something), but the elves don't need to actually run around the city every morning risking being seen by the trash pickup crew and baristas on their way to work.

However, assuming the rules are balanced and make practical sense...

As written, the question is too story-based (where should you mark your portals? That's up to the circumstances of the story and will change for every city and every community). The only plausible answer (that isn't that helpful) is that your network is set up as a "star" with a central location where all portal-pairs have one portal and the others being sprinkled throughout the area/city/community. But what makes sense for one city won't make sense for another. So, your elves own "warehouses" that are full of walls with portals.

All other details are too story-based.


So, some basics first. Your network is made up of portals with an entry and an exit. Where they are located will depend on several things:

  • Any humans nearby would see elves appear out of thin air and disappear back into thin air at portal entrances and exits. So you want them to be in places not frequented by humans. Places like caves, sewers, or just general wilderness would work best.
  • Your elves will want to be just as discreet when setting up the portals as when using them. This is more difficult however. Travelling through portals elves can only be seen at entry and exit points, but when setting them up they can be seen at any point.
  • Portals have a limited top length. The maximum possible length of one portal is limited by the distance one elf can cover in 24 hours (after which point the portal disappears). However, your elves need to eat and sleep (given their magical nature maybe they don't but at least they want to use the portals they created at some point) so in practice that length will be much much shorter. It's set by a distance one elf can cover per certain length of time.
  • You can chain multiple portals to form longer portals. So, a certain location has an exit from portal A and an entrance from portal B right next to it. You can also have branching paths and portal hubs - so next to the exit from portal A you can have entrances to portals B, C and D, all leading to different directions.

So, I think here is how it will work.

Setting up the portals:

This is best done exactly at the start of the witching hour (4 am). At 4 am time stops for an hour for anything non-magical (including humans, at least non-magical ones) but not the magical elves. So your elves have an hour during which they can set up the portal without fear of being spotted by humans.

Since time is limited, this will have to be a very carefully choreographed process. Each elf is responsible for 'their' section of the portal. So, Annie the Elf is responsible for portal A, while Bob the Elf is responsible for portal B. At exactly 4am, Annie has to be in position at the entrance of portal A while Bob has to be waiting at the entrance of portal B. Just as the portals disappear, Annie has to start running like hell to the intended exit of portal A, while at the same time Bob has to leg it to the intended exit of portal B. The length of the portal is determined by the distance that the elf creating it is able to cover in an hour. If your elves can use bicycles, cars or magical reindeer instead of running, length of each portal increases. Once the portals are created, Annie and Bob as well as all the other elves can use them to and go about their normal business.

Portal layout

This will depend on the number and locations of hubs that the elves want to link, as well as the number of elves that are able and willing to create portals. If you want to conver the maximum possible distance, you want a single line of portals linking all the hubs elf want to cover. But you should consider this:

  • Redundancy. In a single line portal system, all it takes is one elf not completing their portal for whatever reason to take out the whole portal network for a whole day. So you may want something like this: You have locations A and B and B and C linked by portals. Add another portal between A and C. That way if one of the portals is out of action for whatever reason (e.g. because pesky humans are hanging around an entrance or an exit) you can still get to your destination using the other two.

  • Hubs. Even if travel through portals is instantaneous, you still want to limit the number of portals you jump through, to reduce the chance of being seen near exits and entrances. So you might want to have hubs, like exit of portal A linking to entrances to portals B, C and D.

If you want to go into more depth (or at least if you're still reading this) you could research the principles used in setting the layout of transportation or computer networks.


Step one: Elves should partner up anybody who can walk more freely in human society

Get allies. More specifically, allies who can move freely among humans. Be that actual humans, or a supernatural creature that can pass well enough for a human. As long as they are loyal and secretive, there should not be much cause to worry.

If extra help is needed to find such people: snow elves probably get some benefit from setting up the portals. The allies might simply be paid workers. There could be a false front hiring them.

Step two: prepare large reasonably flat surfaces

The elves touch them with one hand.

These might differ depending on needs. A manhole cover, a large cardboard cutout, doors, maybe posters if that is applicable. Everyday non-suspicious flat items that are large enough to house a portal.

Step three: allies deliver these around town

Dressed as delivery or repair men. Or maybe actually hired to do deliveries and repairs. They can swap a manhole cover for one with a lingering portal, or attach new flat things in non-obvious areas. As long as they do not go to actual restricted areas, the public will not bat an eye. Just another worker doing whatever they do.

Step five plus: elves activate the portals

The elves would be be located in one or more hubs. Depends on this needs to be set up but the end result is the same. They touch another surface nearby with their other hand (probably a wall prepared to house portals) and command when portals open and close.

The delivered end of the portals can be installed in sewers, in abandoned buildings, or just a place privately hired (a garage might be inconspicuous), in public bathrooms (like in metro stations, for example), etc. to give the best access for the snow elves and whoever else they allow to use the portals.

If some surveillance is installed at the other end, the snow elves could just have a row of monitors to keep track of the other end of portals and open and close them as needed.

This should happen as soon as it is possible to set up the portals again. If it is 4AM, then that is when the allies should make their ways to the snow elves' hubs to collect the portals for the day. The old ones can probably just be brought back. For example, if it is a door in an abandoned building being replaced, then the old door can be brought back to be turned into a portal the next day.

Each ally can probably deliver, let's say, ten portals. Depends on what they are. Replacing a door probably takes more time than simply propping up a large piece of cardboard. However, different items would look inconspicuous at different locations. Also depends on how many locations are to be delivered to, distance, etc. However, 10 portals delivered per ally is probably a good average to work off of. It should be doable within reasonable time limit: hour to hour and a half for the network to be up and operational. Scale the operation up or down per needed - add more allies if more portals are to be delivered or it is harder to deliver them (gaining access to some place might take time and effort).


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