I often write boxed text for new in-game events and locations. I find it easier to think through the sights, smells, and other sensations during GM prep and write them out, rather than improv’ing when I’m trying to write a game. Here’s one such moment.
After several hours’ travels, as you make your way around fallen rock and collapsed tunnels, you are once again outside. You seem to be high in the mountains, though not atop a peak. A massive set of stone doors, much like the one you used to enter the Damycian Underdark leads up into the outside again, onto a rocky trail cutting through a narrow gorge in one of the mountains.
The road goes on for a few miles until you step out of the gorge. Before you, you see a massive ledge jutting off one side of the mountain. Below you, you can see the southern end of the Damycian Mountains taper off, and open sea washes upon a distant shoreline at the end of the peninsula.
In the center of this ledge, on top of a rocky hill, you see an open domed structure made of white marble. Columns, worn and chipped from the wind, ring the edge of it. You hear the crackle and hum of latent magic as a small portal, now reduced to the size of a slit torn into reality, stands open in the middle.
Toward the left side of the ledge, tucked under a rock outcropping with a small cave carved into it, you see Imperial expedition tents set up around the remains of a fire ring. A set of iron poles are set up around it, with an empty cooking pot.