Good morning and salutations!

My name is Daniel and I am a mapper. I have been a mapper for well on 15 years now; however, I have never been able to grasp control of it to better myself.

Recently, I have found my way to an rpg site called roll20.net This is a great site for online gaming and I am in mappers heaven so to speak (or hell depending on how you look at it lol). Without a lot of experience (despite the 15+ years), my maps tend to be fairly rudimentary. They look good enough when I used the in-site objects and such, but i want to advance and find a program that will allow me to load say a hollow outline of Britain, and then make all my modifications to THAT map.

If anyone can help me with this it would be greatly appreciated.