There is a secret tunnel beneath the Bright River Brickworks that exits into the Dry Veins. There is an encounter here pages (30-31) but no map. What has anyone else used for that encounter?
Yea, they missed that. But any suitable tunnel-like layout will do.
Recall that the tunnel connects to what used to be canals and are now the Dry Veins, the area now used for interring the recently dead from Wati. Ossuary-like décor and descriptives would be wholly appropriate to set the tone.