Floors 3 thru 6 of the step pyramid ruin have been mined away over the ages. Level 6 is mostly supposition, not the original state mapped on previous map (#4) of cut away side view of ruin from topside previously posted.
The hole the ruin is in when found by the party. The perfect straight square lines underground are the original walls that have been mined for building materials since.
The battle map of ruin, originally the DM map, hence used for battle as being most accurate. Bugbear, orcs, goblins all dispatched. Zippy the quickling was captured by Sunset Moon revealing her true form, a copper dragon. First treasure score.
This map has a logarithmic scaled scale that starts magnified at the bottom and is compressed towards the top. Right click and open in new tab to see larger vers. Expanded, detailed, and color versions pending.