How far you can travel depends on how many movement points your party has available. If you choose a movement speed of cautious you will normally have 15 movement points, at normal 21 points and at fast 26 points.
Certain things can reduce or increase movement points; for example injuries can slow you down while horses speed you up. You will be told on your turn report how many movement points you have available for your next turn

North = 1
North East = 2
East = 3
South East = 4
South = 5
South West = 6
West = 7
North West = 8