Getting an Idea on how this was done

[Falconius]

He probably traced the waterlines off of a satellite image or some other map altering them as he saw fit. But really with such a general question as "how was it made" the answer is obvious. He drew it.

[Freodin]

I would like to learn how it was made

With a lot of work and patience, it seems.

What I would do if I had to replicate this style of map...

1. Find an existing map of the area I want to map.
2. Cut and scale it to the precise region and size I want it to be.
3. Trace the features that I want to take directly from the original map. In this case, the coastline, lakes and rivers. I will do it by hand, because it gives better results than the stroking methods inplemented in PS or GIMP.
If you have questions about how to best trace those features, just ask.
4. Paint the water blue. Here you can work with selections, adjusting them and filling them in... still with all these little lakes it might be a lot of work to get it completely right.
5. Colour in the major features... in case of this map, forested and praerie areas.
6. Place icons for the points of interest.
7. Place your labels.

That should be all.

[Vooddoo-fire]

Ok thank you for the comments i did not think of traceing in gimp ill give that a try.....

[lobster]

Author of the map here. Hello.

As someone guessed the map was hand traced using a tablet. No procedural stuff here. Just a few nights of manual work.

The underlaying map was collated from several GMaps images and tweaked to keep the original game map's proportions and have a bit more geographical accuracy at the same time.

As to the process of actual drawing is rather simple. It goes something like this:
1. Trace lineart for the waterways, lakes, shoreline,etc. If the underlying map is well done this should not take much time. This is even easier with a map less filled with tiny lakes.
2. Do a masking layer for the landmass. Here a lot of tweaking and error fixing is inevitable.
3. Using the mask make a layer for each color you are going to need.
4. Make irregular cookie cutter shapes to build the border of forest. Lots of copy pasting required.
5. A hex layer is easy to do either as pattern fill or by using any of the ones available online.
6. Design map symbols to fit your needs. Mine are inspired by Fallout series but done in BW for high contrast and usability.
7. Label things.
8. Do a map key from elements of the map.

[Vooddoo-fire]

Thanks i am starting a map project useing this method thank you for the reply