From the publisher:
The musty tunnel winds up, turns and disappears in the darkness. On one side of the tunnel you can see a large passage entirely covered by white cobwebs.
Three caverns jointed in the middle form the giant spider’s nest. The first one is an entrance cavern, filled with cobwebs and nothing much more. The second cavern is the spider’s nest; here the hideous creature stocks its victims by wrapping them in its sticky webs. Some of them are still visible beside a large web; also the floor of this cavern is covered by dozens of perfectly cleaned bones, grim witness of the spider’s past meals. The last cavern features a spring falling from the rocks; some moss and plants grow here.
Some adventure ideas involving the nest:
While the PCs are exploring some caverns they encounter a man who makes few steps and dies. The man has been poisoned, as clearly indicates a large two-holes wound on his neck. The man also held a piece of parchment in his left hand. The parchment is an old map that shows the location of a great treasure near the spider’s nest. The PCs must find the nest and get rid of the spider in order to gain the treasure.
The PCs explore the spider’s nest and find nothing; despite the cobwebs and the corpses in the northern cavern, it looks like no spider is here except some tiny harmless spiders. The water of pool in the southern cavern function like a reduce potion. The now tiny spiders drunk from the pool and have been reduced, but they will return to giant size soon…