At the top of the map, I went north through the tunnel to the area where Morkin is captured but I can't return back south through the tunner. When I enter the tunnel it only goes north and to the south it has a staircase that takes you out. The north passage just goes a short distance north and then east before ending.

How can I go South to return back to the main part of the map?

Thanks

Simon

You need to enter a different tunnel and walk a long way to get out.

OK, thanks. I will try to find another entrance then.

In the C64 version it is exacltly the same. A bit annoying when you have already killed Shareth, other enemies are not a problem anymore and you have just to go back to the Gate of Varenorn

And the passage if blocked by enemies, so to be on the safe side you have to stop every time you see enemies and wait until the next day.
I hated the tunnels in DD since the AI players couldn't use them. So you could just have Luxor and Rorthron enter a tunnel, and then hit Night until Shareth got herself killed.