This was a very local thing, although strangers also technically had to go through it. Because the phenomenon of the passage was so poorly understood by those who weren't specialists in it, the main gate had been barred off, and there was a taboo against the true experience as it was evil. I was trying to get a look through the barred door, but there were non-locals there who started hissing stuff about me for being too interested in it, so I wandered off, disappointed.
There were two ways to go through the "tourist" one. But there weren't any instructions, so I started going through the place. There was someone with me, another woman, and she started having a hard time as we were walking. The area was a great big long room, with its end out of sight; I think the room twisted and had hills. It was divided into sections with different colors and views as you walked through, with flexible iron chain mesh descending from the ceiling. Each separate area triggered a different set of emotions, skills, and memories. I was struggling too, and my companion was finding it hellish. Exhausted, we staggered out, into the employee break room, which was occupied by several chattering and smoking locals.
They let me know that yeah, we'd survived it, and there was a separate hallway skirting the actual active area for those who couldn't handle it, we'd gone through backwards, and we'd actually had something tougher than the version that the locals typically took, because we hadn't gone in prepared for it, and yeah, if you weren't prepared, the emotional wringer would seriously fuck you up for a while, and that was why it was considered evil. We went through again, better-prepared, and properly, and in order, it was still a Significant Experience, but it was not Terrible.