Dungeon Mapping

Patrick (Renovating the Temple) asked me how I created the maps I use for my Montporte Dungeon campaign. I use AutoREALM, a free RPG mapping software package. Given my experience with cartographic and GIS programs, it has been a fairly easy program to use. While creating maps can be a bit tedious in AutoREALM (at least compared to drawing them by hand), I can save the final products as JPEG files so that they are ready to go with a virtual tabletop program.
Map A
Dungeon Maps for Gameplay
We use Roll20 or Fantasy Grounds, so it is great having a map in JPEG format that can be uploaded into whatever VTT we happen to be using. All of my dungeon maps represent 300' x 300', the same size as the Stonehell Dungeon maps. My scale of choice is each square representing 5'. I find that this scale works perfect with virtual figures or pogs, so that the map can double as an online battlemap. The map above (Map A) is actually a composite of four JPEG files.
Map B
I start with the above template (Map B). The first thing that I do is mark any of the corridors or other features that come into the the map from adjacent maps. I do the same thing with stairs or other features that connect with levels above and below. Then I superimpose the map I am working on with the adjacent maps, just to double-check the alignment 

For regular dungeon features, I draw straight lines and use the AutoREALM snap grid feature to line them up with the grid. I use the draw polygon function to fill in the spaces between the rooms/corridors. For caverns and other irregular features, I use the freehand drawing feature and draw closed shapes. I keep doing that until I get the features I want. You can see the results of both methods on Map A above.

In order to publish the maps on my blog, I first create a Publisher file and line up the JPEG map files next to each other. Then I draw and fill black squares to cover up the unexplored areas. I save the resultant map as a JPEG file and crop it. That is how I created Map A above; it is a composite of four separate JPEG maps with the unexplored areas covered and cropped.

Other AutoREALM Maps
I am not particularly good at creating maps in AutoREALM, mainly because I haven't spent enough time playing around with it. I created the following maps for my Castles & Crusades Emmon Campaign.
Map C: Elbow Bay
Map D: Sali Isle
Map E: Village of Melford
I had two different groups of players for the Emmon Campaign. One group started in Melford (Map E) where I used a number of modules from Dragonsfoot (The Melford Murder was a huge success!). The second group started on a small island, where I used Death Frost Doom. The results of that adventure forced the player characters to flee the island and they ended up in Elbow Bay (Map C).