Awesome :) Fantasy map making is another hobby of mine.

This is the exact emotion I want to convey with my maps and why I like to do watersheds! We're all part of some amazing inter-connecting system that most people never even realize. Thank you!

For this one I used the USGS 1 Arc Second dataset which gives about 30m resolution. The GEBCO dataset is also a good option.

Raven Maps does stellar work and are one of my inspirations. They balance traditional cartography and art perfectly! One thing I'd like to add to my maps in the future is labeling which they do very well.

PS - I like your username. I identify with it a little too much sometimes!

Thanks!

Thanks! Glad you like it :)

The short answer is aesthetics.

The longer answer is its a technique found in a lot of older maps which maximizes the area of interest (in this case the Columbia River Watershed). By letting portions of the area of interest hang over the edge of the map, you can increase the scale without adding a ton of additional white space.

As did I!

Correct. The Snake River is toward the bottom curving around and flowing west and north toward the Columbia.