On Antiquated Lands

Here's a bit of background about the world. It is very dry, but I enjoy that type of stuff.

On Antiquated Lands

Rules on Running

So, we have mentioned the run rules at the table, but nobody has used them yet.

Running

You can run as a full-round action. If you do, you do not also get a 5-foot step. When you run, you can move up to four times your speed in a straight line (or three times your speed if you're in heavy armor). You lose any Dexterity bonus to AC unless you have the Run feat.

You can run for a number of rounds equal to your Constitution score, but after that you must make a DC 10 Constitution check to continue running. You must check again each round in which you continue to run, and the DC of this check increases by 1 for each check you have made. When you fail this check, you must stop running. A character who has run to his limit must rest for 1 minute (10 rounds) before running again. During a rest period, a character can move no faster than a normal move action.

You can't run across difficult terrain or if you can't see where you're going.

A run represents a speed of about 13 miles per hour for an unencumbered human.