Bridge

Soviet tanks by Mir, T-34/76.

One platoon sits in overwatch while the other platoon crosses the bridge.

The tanks don't bunch up.

Too close and the pontoons can't carry the weight.

Drive slow over the bridge.

Then ease off the ramp.

Hang back a bit while the other tank is on the ramp.  You don't want to slide into him.

This extended bridge has two roadway sections.

Lots of rivers in Europe.

It has four pontoons.

Bridge

The pontoon bridge is generic enough to work for most any period.

In the days of horse cavalry the roadway and ramps were often covered with dirt and straw.

It gave better footing to the horses than smooth boards.

Total span is about 10 inches.

WWII Cossacks in German service.

Pontoon Bridge

I finished my pontoon project.

These are the five parts needed to make a simple bridge.  Two ramps, one roadway, and two pontoons.

Pontoons are clipped onto the bottom of the roadway.

Ramps are added at each end.

The poles are added to help keep the roadway in place and because in real life they would have a rope strung between them as a railing.

Allow tanks to cross the river.