1. Suspension bridges hold cars up using giant hanging cables. Bridges like the Golden Gate Bridge are called suspension bridges. They hang from massive steel cables strung between tall towers, letting them stretch across wide ocean bays where pillars can't touch the bottom.

2. Drawbridges open up to let giant ships sail right through. Movable bridges have roadway sections that can lift up, swing open, or slide away. This lets tall cargo ships and sailboats cruise underneath without crashing into the bridge deck!

3. Ants build living bridges with their own bodies. When army ants need to cross a gap or a puddle, they link their legs and bodies together to build a living suspension bridge for the rest of the colony and their queen to march across!

4. The Lake Pontchartrain Causeway is like a bridge marathon. Located in Louisiana, this incredible bridge is so long that when you drive across it, you can't see land in any direction for over 24 miles (38 kilometers)—it feels like driving across the middle of the ocean!

5. Truss bridges look like giant geometric jungle gyms. If you look at the sides of many train bridges, you'll see a repeating pattern of triangles made of steel beams. Triangles are the strongest shape in engineering because they don't bend or warp easily under heavy weight.

6. Beam bridges are the simplest kind of bridge. A basic beam bridge is just a rigid flat board or slab laid straight across two supports—just like placing a wooden plank across a little creek in your backyard!

7. Trolls used to live under bridges in fairy tales. In old European folk tales and fairy tales, grumpy monsters called trolls loved hiding in the dark, shadowy space underneath stone bridge arches to stop travelers and demand toll fees!