"Two days later your arrive at the camp. It's a logging camp, so you've spent most of the last two days following a packed dirt road up into the hills. The hills have gotten steeper and the road has gotten more winding as you progress. It's late in the day and the woodcutters are just trooping back into the camp when you arrive.
The camp occupies a good-sized clearing and has obviously been here for some time; the buildings are wood, with solid walls and angled roofs which have been coated with some kind of bright-colored lacquer to make them weatherproof. The wood walls are less colorful, but they share a uniform golden shine that suggests some kind of care and treatment. All in all, it doesn't look like a bad place to work.
The troopmaster hurries over as the wagons pull up and stop. He's an older human male, with a large belly but solid, muscular shoulders. His head is bald, but a thick red beard falls to the middle of his chest. He recognizes lord Ardivil immediately, and offers respectful greetings."
"The buildings of the camp are even more comfortable than they seem from the outside. The woodcutters have clearly been allowed to decorate, and various scenes have been painted with various levels of skill on the inside walls. The woodcutters share a pair of large barracks-like buildings at one end of the camp, while the four overseers share a smaller building nearby. The troopmaster has a building of his own, an office with living quarters in the back. Cut trees are stored in a large, open-sided pavilion on the far side of the camp until they can be loaded onto wagons and sent back to the main warehouse in Stalmont. There is another large building that holds supplies and equipment, and in the center of the camp is the dining hall: a building every bit as large as the supplyhouse, with a wide covered porch along one side.
The woodcutters are mostly human, but you see a couple of elves, three gnomes, a single dwarf, and a giant half-orc who slouches along so as not to overtower his companions. Two of the overseers are human, while one is an elf and the last seems to be half-and-half. It's not immediately obvious how many are men and how many are women; everyone out here has their hair cut short, and their faces are dark and rough from sun and weather.
Lord Ardivil's arrival is greeted with excitement, especially since he's brought barrels of dried fruits and vegetables, wheels of cheese, and other niceties of civilization that aren't always available out here. A few of the woodcutters complain that they won't get to eat any of that until tomorrow, since dinner was already prepared, but even the complaints seem fairly good-natured.
Lord Ardivil and Expedition Leader Victoria will have the extra rooms in the overseers' building, while you and the drivers will be sleeping in the barracks with the woodcutters.
The troopmaster, whose name turns out to be Durrel, explains all this while he leads you into the dining hall and over to the food line, where you fill your trays and follow him to a table. Dinner is some sort of meat in a mild cream sauce, along with spearplant and dark bread. It's plain, but filling. As you eat, he explains how they discovered the ruins.
The dirt road that leads to the camp actually continues on the other side further up into the hills. Everybody assumed that was just for logging further back in, but a few weeks ago one of the gnomes got curious and on rest-day she and her friends decided to follow it as far as they could. Turns out the road goes all the way back to the edge of the mountains, and right there at the first big cliff there's another clearing with a bunch of big stone buildings. And there are rooms cut back into the side of the mountain. So they explored a little bit, wondering if maybe we should move the camp up there or use the ruins as a second camp. Well, word got around pretty fast when they got back, so I figured I should send a team up to really look around. And what they found was that the rooms cut into the mountain also have doors in back, doors that open into a kind of connecting hall. And that connecting hall leads back into a giant cavern further inside the mountain... and there's a whole city back there.
So we pulled everybody out, and sent word to the owners. It seemed like the smart thing to do. Bulora, the dwarf, tells me the stonework is very old -- but between being simple and solid, and having been out in the weather for centuries, she can't tell who might have built it. Laremin, over there -- the elf overseer -- led the search party, and after looking over the ruins he thinks there's an old stone road somewhere under the dirt road. He says that's why the trees haven't grown over it. And that's really all I can tell you about it."
In the morning the party and lord Ardivil walk the half-mile up the trail, and get their first glimpse of the ruins.
The buildings formed a rough half-circle out from the edge of the cliffs. Not much was left: just stone walls and paving stones, and even the paving stones were beginning to give way to the forest. Stray blades of grass had wedged themselves in between the stones, and here and there a stunted tree had forced its way up as well, shoving the stones aside. There was no sign of whatever furnishings the stone frames of the buildings must once have had: no remains of roofs, no frames for doors or windows in the openings in the walls. The insides had accumulated layers of windblown dirt and leaves along with a fair amount of moss and lichen, enough to allow the occasional patch of grass, single flower, or even a small tree in the corners of the buildings.
The party checked carefully, but found no sign of danger: nothing more than small forest animals around and the slowly-conquering plants. With the outer buildings explored, they checked the cliff-face openings. Most likely those were dwellings: the rooms were small, no more than twenty feet by thirty, but fireplaces and shelves had been carved out of the stone. And on the far side of the room was another doorway, which led to a small area that was probably used for storage, and then on to a cross-tunnel that led to the connecting hall that troopmaster Durrell had described earlier. The hall was strangely undecorated: the stone skillfully carved, but with no statues, no reliefs, no little flourishes in the stonework. Firstborn's paladin, Lithos, speculated that perhaps the walls had been covered in murals and they'd simply been covered by a layer of dust or faded away over time.
The connecting hall was forty feet across, with two rows of columns that marched back along its length. The party followed it to its end, where it emerged onto a broad balcony overlooking the underground city.
The city occupied the bottom half of a roughly spherical cavern, with rows of buildings marching down in steps to the bottom center. There was a larger structure down there, but between the distance and the darkness and the fact that everything here was the same color of stone it was hard to make out. The city wasn't completely without light, though: small, flickering lights drifted through the air of the cavern, shining and disappearing and shining again. From their place on the balcony, nobody could tell whether these were animals, spirits, or some sorcerous sort of lighting. The entire place was eerily silent; the only thing the party could hear was themselves. After a time, lord Ardivil suggested that they head back. The group agreed that it seemed safe enough to bring a wagon up to the outer ruins and establish a camp there, which could serve as a base of operations for exploring the city. They were an hour's walk from the logging camp, so they could always pull back if they discovered some danger.
...And that was where we left it. It wasn't the most exciting episode I've ever run, but all this is background and set up for the things that come next, which... well, our bold adventurers will just have to wait and see.