Cartographers' Guild

"Hexagons are the perfect shape, I tell you! Not circles! Not Squares! Not Octagons! Hexagons!"

--Trunkeen Halverstaff, Dwarven Leader of the Cartographer's Guild

In the Game
The Cartographer's Guild is an important spot for adventurers. With an office adjoining The Brass Dragon, the guild is home to the mapmakers and meteorologists who track the movements of Mirosia's many islands. Adventurers and captains setting out to explore first stop here, to learn changes in the locations of islands and predict safe routes around storms and other hazards. The guild is busy and bustling at all hours of the day, and mostly bothers to track locations of islands and major threats to Mirosia's safety, like Limbo fields and certain Shadowfell Islands or drifting dragon's lairs.

You can use the guild during your sessions as a way for players to plan a route to an island, and get basic information about places they want to visit. A lot of information isn't available here, though - players might be better off asking others at The Brass Dragon or simply going there themselves.

The Mapping System
The Guild insists that mapping of Mirosia be done with hexagonal grids. The standard largest scale they use is a 6-mile hexagon, as these proportions scale well in several senses.

Any linear path between the vertices or faces of a hexagon of that scale has a predictable, simple distance that is roughly accurate. The predictable nature of this shape makes it work well as simple abstraction that most people can understand in regards to the location of islands, and makes it easy to form a quick path.
 * 7 miles to a vertex directly opposite that forms a trapezoid.
 * 6 miles to a vertex across that forms an obtuse triangle.
 * 3.5 miles from vertex to center, or 3.5 mile long edges. 6mihex.jpg

When making a more precise map of an island, a system of subdivisions is used with more hexagons.
 * The first level of subdivisions forms hexagons a half-mile across. This results in making the larger hexagon 12 hexes across.
 * Each of the half-mile hexagons can be broken into 1/24th mile hexagons.
 * (DMs, note that 1/24th of a mile is roughly 220ft, or roughly 44 5ft squares on a battlemap.)

Resources

 * In Praise of the Six Mile Hex