Susquehanna Township (WHTM) Stretching across the Susquehanna River, a few miles north of Harrisburg, is an engineering marvel-the Rockville Bridge. It has 48 stone arches, each 70 feet from base to base. Its total length is 3820 feet. It is the longest stone masonry arch railroad bridge in the world-and the third railroad bridge erected at this site.

The Pennsylvania Railroad was established in 1846, and by 1847 they were already building their first bridge across the Susquehanna River. It was made of wood, with just one track. The first train crossed over it on September first, 1849.

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But it didn’t take long for increased rail traffic to turn that bridge into a bottleneck. In 1877 it was replaced by an iron bridge with two tracks. But even with the extra track, it wasn’t long before that bridge couldn’t keep up with traffic either.

Then in 1900 the Pennsy started work on a third bridge, the one you see today. (The second bridge continued in use while they built the new bridge; you can see what’s left of the old pilings from the Greenbelt trail, just north of the current bridge.) They built big, with four tracks crossing the river, and they built strong, constructing a stone arch bridge so sturdy it was called “the bridge built to last forever.”

It went into service in 1902, and for decades it handled everything man and mother nature could throw at it-snow, ice, rain, wind, hurricanes, floods, and more and more trains.

Then on August 19, 1997, wear and tear caught up with the Rockville Bridge. A 12-foot by 30 foot section of bridge collapsed, dumping five coal cars and 500 tons of coal into the river. Ironically this happened just as Conrail, the successor to the Pennsylvania Railroad, was contracting for maintenance work.

The damage was repaired, using reinforced concrete molded to look like stone. (It doesn’t match very well.) And now the bridge is well into its second century, as it continues to provide service carrying trains over the Susquehanna River.