As noted by General Amamentena, you find four Maidens of Madura near the entrance to the catacombs, and they are present with food and water for the lot of you for three days.  The entrance is roughly south of the city, in an area where the floor of the cavern has become significantly more uneven.  The women seem uninterested in speaking with you, but note that they have been instructed to stay here and await your return for up to a week, should you actually return.

The actual opening into the catacombs, with the Maidens reluctantly show you, after some prodding, is at the bottom of a rough but wide set of stairs, much of the work seeming to speak of inexpert work done with inadequate tools.  As usual, absent any light source, this area is pitch-black, and even infravision only shows very slight differences in temperature between the air and the stone here.

Voran volunteers to carry the torch.

Roak looks at Vsaati. "Care to lead the way? Voran can go right behind you with the light. And to cure you if you get hurt or something."

Silverglade asks Albricht "Do this stonework look safe to your dwarven eyes?"

"You mean besides the appearance of it being constructed by a three-fingered she-orc drunken on the fermented squeezings of rotten olives? Let me have a look..."

The oldster shuffled his worn sandals across the stones and laid a gnarled hand against the stone, then he leaned in to sniff a little, and finally licked a leathery tongue over the palm of the hand which had rested against the rock as he craned his neck around to inspect...

Dwarven Racial Super Powers: Albricht Burghammer rolled 1 using 1d6 (Success)

The cutpurse wrinkled her nose at Roak's suggestion and then sighed.  "I suppose you did donate a sword to me," she allowed, before sliding forward to the front of the group.  As the reached the top of the uneven stairs and Silverglade prodded Albricht into action, Vsaati made room for the venerable dwarf to do his thing.

Once he had proclaimed the stairs safe Vsaati would lead the group forward into the darkness, relying of course on Voran's trusty light source to guide her way.

Having the use of a mace already Sherborne, while he found the conundrum about the best way to supply and get otherwise ready to move on amusing, was ready to get going and followed along.

Albricht comes to the conclusion that, despite the sloppy work, the stone here is solid enough.  It won't win any prizes of any sort, but should hold for a hundred years or so, at least.

Vsaati finds herself following a passage that begins to slope downward, broken here and there by a short flight of steps where it becomes steeper for a bit.  After perhaps 250 feet, the otherwise enclosed passage opens out into a large gallery, perhaps 60 or 70 feet across.  The light from the torch illuminates several other exits from this room, and a ring of rough benches stand in the middle, perhaps big enough for 20 or so people to sit upon.

Voran, following Vsaati closely, examines the place to see if it had any religious significance.

As Elder Voran looks around the room, he finds the symbols of a lightning bolt, a wand, coins, and a spear here and there, all roughly cut into walls, floor, and benches.