It’s fall in the United States, the season when millions of Americans take to country roads to check out pumpkin patches, apple-cider stands - and covered bridges.

These structures stand year-round, of course, but they take on an especially quaint character against a canopy of vividly colored autumn leaves.

Covered bridges originated in China and can be found throughout Central Europe.  But not in the concentrations you’ll find in America’s Upper Midwest and New England.

Interest in these nostalgic bridges grew in 1992 with the publication of the best-selling book, "The Bridges of Madison County."

Madison County is in Iowa, not far from the midwestern state with the most covered bridges.  

That would be Indiana, with more than 150 of them. And here’s how much Indianans care about them:

Back in 1986, the 19,000 or so people living in rural Rush County would have been alarmed if you told them there were “activists” in their midst.  

But there were, by the hundreds: indignant crusaders who sprang up like summer thunderstorms in towns such as Rushville, Moscow and Homer. 

When they finished, the object of their unhappiness - the three members of the county’s Board of Commissioners - had lost their seats.

That’s because they had approved the destruction of four of the county’s six historic covered bridges in favor of ordinary concrete-and-steel spans.   

Arsonists took care of the oldest and most dilapidated, built in 1873.  But that only heightened the residents’ resolve to save and restore the other five.

The bridges’ elaborately decorated wooden superstructures did more than protect the stream crossings from rot.

Embellished with vinelike wooden tendrils and eye-catching overhung roofs, they resembled country cottages.

Not only did Rush County’s bridge-lovers save the spans, they inspired bridge festivals and bluegrass-music jamborees.

And cars and trucks and tractors still rumble across these picturesque covered bridges, demonstrating that historic structures can be a working part of modern day-to-day life.