Is a permanent teleportation circle only a destination, and not a point of departure?

Question

The 5th-level spell teleportation circle says:

As you cast the spell, you draw a 10-foot-diameter circle on the ground inscribed with sigils that link your location to a permanent teleportation circle of your choice, whose sigil sequence you know and that is on the same plane of existence as you. A shimmering portal opens within the circle you drew and remains open until the end of your next turn.

[...]

You can create a permanent teleportation circle by casting this spell in the same location every day for one year. You need not use the circle to teleport when you cast the spell in this way.

The teleportation circle you draw seems to be a point of departure only when you cast it. When it's a permanent teleportation circle, however, it doesn't mention whether you can use it as a point of departure.

Can permanent teleportation circles only serve as destinations?

Answer 1

Permanent teleportation circles are for creating "custom" teleport destinations, such as a party's home base. Permanent teleportation circles themselves are only destinations, as you said. They don't allow you to teleport from them without casting the Teleportation Circle spell.

Answer 2

A permanent teleportation circle is not a teleportation circle spell

There are some subtle clues in the phrasing of the spell teleportation circle that tells us that the spell teleportation circle and the object 'permanent teleportation circle' are not the same thing.

Firstly, spell names in the text are always in italics. However, the PHB does not say "permanent teleportation circle", but "permanent teleportation circle" without italics. This suggests that a permanent teleportation circle is not a teleportation circle spell with permanent duration but rather something different.

Secondly, the wording in creating a permanent teleportation circle differs from other spells which can be made permanent.

Teleportation circle:

You can create a permanent teleportation circle by casting this spell in the same location every day for one year.

Compare with forbiddance,

If you cast forbiddance every day for 30 days in the same location, the spell lasts until dispelled

And Mordenkainen's Private Sanctum,

Casting this spell in the same spot every day for a year makes this effect permanent.

Or Druid Grove (XGtE),

If you cast this spell in the same area every day for a year, the spell lasts until dispelled.

Or Temple of the Gods (XGtE),

Casting this spell on the same spot every day for a year makes this effect permanent.

Unlike these other spells, teleportation circle does not say 'this spell becomes permanent' or anything along those lines. Rather it says that it creates a permanent teleportation circle.

The spell text for teleportation circle describes what a permanent teleportation circle is. They have unique sigil sequences which can be memorised. They are destinations for teleportation circle spells (and other teleportation spells as described in their own descriptions). They can be created by casting teleportation circle in the same location every day for a year. The rules don't say that permanent teleportation circles do anything other than these things - anything beyond these things is inference.

If you read "permanent teleportation circle" as a teleportation circle spell with duration of Permanent, then you open the question of "where does it teleport to?" which produces all kinds of confusion. However, if you take the care to realise that "permanent teleportation circle" is not a teleportation circle spell but rather a separate but related entity, with a confusingly similar name but very different effects, then all the logical headaches go away. A permanent teleportation circle is a destination, nothing more.

Answer 3

Permanent teleportation circles can only be destinations; HOWEVER, a non-magical permanent "sketch" of a sigil sequence can eliminate the need to have a destination sigil sequence memorized. This means that a network of permanent teleportation circles will have ONE magical permanent teleportation circle, and any number of destination sigil sequences sketched on the floor, that can be traced with the spell components that are subsequently consumed.

The plot hole in this is that if you teleport out to a specific location from the same location every day for a year, it would create a duplicate permanent circle. It's easy enough to just use a different spot on the floor for a few days every now and then, but it still creates the possibility of a quasi-paradox in the form of two destinations with the same sigil sequence. This adds to the oliphant in the room concerning security. If your sigil sequence is known by a single person with ill intent, you now practically have a wide open back door to the bad guys unless you dispel your permanent circle and work for a year to make a new one. On the flip side, if you can make a copy of another circle, the bad guys can possibly make you teleport right into their lair instead. Considering the random element of teleportation magic, as a DM, I would rule that it would be a 50-50 chance.

I suppose you could have several circles under construction at once and just dispel the old one whenever you complete a new one, but that gets expensive and labor intensive, and impractical if you have limited space.

EDIT: Perhaps the casting of the spell is different if your intent is to make it permanent? It's not unprecedented for a single spell to have variations on its casting.

Answer 4

I disagree with some of the thoughts here. Let's start with the sigils. The sigils in your temporary teleportation circle connect your casting location (think coordinates) with sigils that represent the location where the permanent gate is. Based on this, there can only be one location chosen per usage. This means that if made permanent, there is only that one destination permanent circle per permanent circle.

Once made permanent, you don't have to cast again. That's the point of being permanent. It's always open one way.

So how do we get back? You need one on each end, except you can't build them simultaneously aimed at each other based on the rules. You actually would need two permanent circles on one end and one permanent circle on the other for back and forth.

Your first permanent gate can only connect to one you are already are familiar with and know the sigils (address) for. So you can't connect it to your other proposed gate, because it's not built yet. So your first permanent gate connects to someone elses. Once you are finished the first gate, you have your "home" gate with complete sigil address. You then get to the location you actually wanted to connect to by teleport/walking, or whatever. At that location, you make another permanent gate (your 2nd), that will exit to your first gate at home. So now you can go from your destination back to home. Once home, you create your second permanent gate there, to connect to your 2nd gate, the away destination you just got the sigils for. So you leave home by traveling from your gate 3 to gate 2. And return home from Gate 2 to gate 1. We would assume gates 1 and 3 are close by. Or maybe the return gate is in a secured area, so nothing can follow you home.