Question for WWI campaigns

[Mr Grumpy]

Cavalry can only cross rivers via medium or heavy bridges, if you are trying to cross one of these and you cannot maybe you have exceeded the road stacking limit across the bridge (2600)?

There is no difference between the effects of canals or rivers, they can only be crossed in F14 by the bridges on the map or a bridge created by a bridging engineer unit.

So yes rivers/canals are major barriers for the attacker especially if bridges are scarce.

Obstacles do not effect the stacking limit, here are the rest of their effects.......

Unpenetrated Obstacle hexes cost the full movement allowance of units to enter but cause no casualties. Obstacles do not block supply. Obstacles
are considered Penetrated after any unit enters them and from that point on,
their cost depends on the status of the entering unit:
• It costs Deployed units an additional ¼ of their full movement
allowance to enter Penetrated Obstacle hexes.
• Units in Travel Mode have no additional cost to enter Penetrated
Obstacle hexes but cannot do so using Road Movement.