What medium is this map drawn in?

[Crayons]

It's almost certainly all drawn by hand either with pen and paper or a graphics tablet. If you look at the text, it's very neat indeed, but not perfect as it would be using an electronic font. Certainly not the capitalized text which appears to be almost deliberately "naive".
The whole drawing was then probably resized down by a factor of about a half I would estimate. Either as part of a scanning process or in something like Paintshop Pro using "smartsize".
If your major problem emulating this style is the handwritten text then try using a font like Amiene, Bradley Hand ITC or Pristina.

[ShadowStalker]

Thanks, those fonts would work perfect. I can "draw" the bolder, capitalized text but not the simple italicized text for the city names. Would you recommend mixing text formats (like hand-written and PS fonts), or would you stick to just one format?

[RobA]

Thanks, those fonts would work perfect. I can "draw" the bolder, capitalized text but not the simple italicized text for the city names. Would you recommend mixing text formats (like hand-written and PS fonts), or would you stick to just one format?

I'd keep them consistent.

Also, from the provided link the artist is Richard Geiger (RG not RS, oops).

-Rob A>