Everyone knows the most famous mule on the Erie Canal was named Sal. But how many folks know what the heck a mule was doing alongside the waterway?

The answer to that question might lie in the visitation numbers for the Canal Experience, an unheralded living history museum on the edges of Toledo. The museum complex includes a general store, working mill, and – most thrillingly for transit buffs – a mule-drawn state packet boat.

As costumed interpreters aboard The Volunteer hourly explain, mules were recruited to pull boats down canals like the Miami & Erie Canal, which connected northeast Ohio to Cincinnati, since no machinery then existed to power the massive vehicles. (The mules, it’s worth noting, rarely got wet: They slogged along dirt towpaths on the canal’s banks.)

 Even by nineteenth-century standards, mules were aggravatingly slow. Most mules were out of work by the early 1900s, displaced by fast-moving trains and automobiles.

But in Grand Rapids, Ohio, where every summer a crew of mules take turns lugging visitors through one of the nation’s last remaining limestone locks, the job market for mules has remained strong. (Although only mules willing to be petted by summer campers, walk eight miles and wear 1876-era getup need apply.)