He keeps going. If he can't meet a metal head today, so be it, he can try again tomorrow. He went out armed and armored, if he meets one and it won't talk. It's nice to get some fresh air.

Will this pass take him out of the city?

The automated system guarding the gate will open it for him. It opens onto a grassy ledge with a sheer cliff into a deep ravine. Across the ravine is a much taller cliff with some kind of structure on it in the distance. It's a very mountainous area and sheer cliffs likewise pen him in on the ledge.

There's a ring set up near the gate carved with ancient writing; something blue and insubstantial swirls in the middle. There's a matching one up on the other side of the ravine. There's a floating platform hovering in the ravine - not much like the floating platforms at the hospital, as though not built to the same standards or with the same constraints, but still a floating platform. He could step onto it. He could step through the ring - or given how it's set up on a stand that keeps it above the ground, he could probably jump through it more easily.

Comprehend Languages hasn't even worn off yet. What does the writing say?

It just says "life" over and over all around the circle.

Can he get across the ravine, if he steps on the platform and then continues to the other side?

Absolutely not. The other side is over his head from here in addition to the ravine being very wide and the platform very small.

Well, it does float, and right now it's hovering in place but perhaps it doesn't do that all the time. Can he find a rock to put on it?

He can find a rock.

When a heavy enough weight settles firmly enough in place on the platform it takes off along the ravine and into a cave where it disappears.

...does it come back?

Not promptly.

He detects magic on the ring.

Well, it's not exactly what it would look like if a wizard from Golarion made a teleportation circle, but there is a certain resemblance.

He's never seen a teleportation circle, but... hm.

He tosses a (smaller) rock through it.

It does not come out the other side. There is a faint distant thump on the grass on the other side of the ravine, probably not very audible from such a distance for a normal human.

...he doesn't have Light today, just the Detects and Guidance and Mending.

Can he find a loooong stick and poke it through?

Not without damaging a tree for it, though there's a small tree on this grassy ledge that perhaps he could break something off of.

Yeah, he'll take a branch and poke through the wibbly-Conjuration-aura circle.

While it stays in his hand and he stays firmly on his side of the ring it just feels like he's pushing through faint vibrations and slight resistance.  The blueness increases in opacity to slightly swallow the end of the stick.

He puts Detect Magic back up again and stares while he lets go of the stick.

The stick magically vanishes and can just be seen falling from the other ring.

Someone put up a permanent gate and it goes across a ravine that could just as easily be traversed with a bridge and nobody has stolen the rings and put them somewhere less stupid.

Well. He'll go through now.

Now he is on a different cliff. Here is his stick. Here is his rock. It's a nice grassy cliff with some ferns and the only path forward runs between two even taller cliffs for a few feet. There's a gap and another sheer drop and a view of a waterfall and a huge ancient building with glowing parts and more grass and trees. There's a much narrower ravine with another floating platform in the middle. He could absolutely traverse this one by jumping onto the platform and then to the other side, which is an ancient structure of the same brown metal as the huge building and the teleport rings.

Or rather, he could do that if the floating platform were not floating with its flat side down and its pointy side up.

There are grunts and nonhuman footsteps and metal noises.

Guidance.

Voluminous Vocabulary - ah, he didn't quite get it, next time maybe - it's still good for the one language.

Guidance again.

Standing still, trying to school his heartbeat.

The sounds change. The metal heads ready themselves, somewhere out of sight, now that they've heard a human voice.