Obstacles are things like hedges, fences, walls and trenches that troops must clamber over to cross.

It takes a model half of its move to cross an obstacle. So if a model has a move of 4" it must surrender 2" to cross a hedge or a wall. If a model has insufficient move left to cross an obstacle it must halt in front of it. The model does not count as half way across if it has 1" remaining, for example. Where an entire unit of troops is attempting to cross an obstacle the penalty continues to apply while any of the models are crossing.

It is perfectly possible for part of a unit to end up on one side of a linear obstacle and another part to be on the far side. This is fine. Place the part of the unit which can cross on the far side of the obstacle and leave the part that could not cross on the other side. As long as the ranks on both sides are in contact with the obstacle this is perfectly acceptable.

When it moves from this position the ranks must be returned to base to base contact. The unit can still only move at half speed until all the ranks have crossed.

If a wall, hedge or fence has a gate in it then it is assumed to be open unless otherwise agreed, and troops may move through the gate as normal.

The penalties for difficult terrain types and obstacles are cumulative. If troops are moving at half rate of 2" across difficult terrain, then they must surrender half their remaining move, a further 1" in this case, to cross an obstacle.