Bridges and bridges

[The SNAFU]

Snafu,
Remember you can ferry infantry across the river to create a bridgehead. Select a point where such a buffer would prevent the defender from observing the bridge work, cover the bridgehead with loads of artillery and you will get across even under the worst conditions.

Dog Soldier

Dog Soldier,

I dont understand. Dont you need a ferry or ferry hex to move troops across water without a bridge? Im sure I missed it but I looked through the manual and dont see any reference like that.