From time to time, we've told you about America's vast interstate highway system. But the nation's first superhighway was not even a road. The Erie Canal across New York State opened more than 100 years before the first paved expressway was built. And VOA's Ted Landphair says the canal is still open, but only to travelers who like to take things slow.

Ted Curtis owns an excursion boat, the Sam Patch. It runs on the Genesee River out of Rochester, then onto the Erie Canal. He says the original, narrow, hand-dug canal opened the West, magically connecting the prosperous Hudson River Valley in the east with Buffalo and the Great Lakes, 400 kilometers to the west. This engineering marvel tamed or bypassed rushing rivers and waterfalls and made New York City America's commercial giant.

Mules plodding along the old canal towpath pulled barges loaded with grain and ore going east, or coal and manufactured goods going west, across New York State. But soon, much speedier railroads stole away most of the freight business.

"There were a couple of times when it looked like they were just going to shut the canal down. Railway was taking all the freight. But by God, it's still there, still functioning," says Mr. Curtis. "Most of it today is recreational and tourism and people's private boats. By the end of September, we'll be seeing a lot of traffic. It's the boats from Chicago and Detroit and Thunder Bay [Ontario] and Duluth [Minnesota], coming down the lakes, through the canal, into the Hudson and the Intercoastal Waterway, and going to Florida for the winter. And then in May, they'll all come right on back up."

"In the 21st century, it's a very calm, peaceful way to get out into nature, to hear the birds, to see the deer. It's a very, very restful experience," says Ruth Naparsteck, the City of Rochester's official historian. "But it wasn't long ago when you could go out on the canal, and you might experience, maybe, going over the embankment."

Or through it, as the captain of a boat called the Bluebird discovered late one night.

"Because of groundhogs ferreting into the wall, the side of the canal actually burst," says Ms. Naparsteck. "This captain and his wife were just carried off and in daylight found themselves in a tipped-over boat out in a cornfield."

Passengers on the Sam Patch - like Jim and Brenda Whitehead, visiting from Tennessee - get a much more placid trip today.

"I've always heard of the Erie Canal and thought we'd come up and take a look at it," Jim said. "It's very interesting, and we're enjoying the day. This is a great place to be a boater."

"It's a nice, leisurely cruise," said Brenda. "Life is too fast-paced. It's time to take a little break here."

The Whiteheads picked the right place. The posted speed limit on the canal, which is open from May 1 through November 15, is just 16 kilometers an hour. A journey from Buffalo to Albany, stopping at all 35 locks along the way, takes five or six days. Bikers who now share the towpath with hikers go faster! The fee to take your boat on the water varies from $5 to $100, depending on the length of your vessel and your journey.

If you DO navigate the Erie Canal around Rochester, you'll maneuver through Lock 32 as chief operator Kevin Lynch raises or lowers the water level almost eight meters before sending you on your way.

"I'm going to open up these lower valves and let the water out of the lock," says Mr. Lynch. "So it's like pullin' the plug on a bathtub now. Open the lower valves up, and the water'll come up from the discharges down below."

Why is the lock there at all?

"The Erie Canal starts out a foot above sea level, and by the time it makes it to the Niagara River up by Buffalo, it's 584 feet above sea level," Kevin Lynch says. "So it depends on where you're located in New York State and what terrain you're at. This lock here happens to be 25 feet difference in water level."

Landphair: "So if you didn't have locks... "

Lynch: "It'd be one big current. You'd never be able to make it up there [to Buffalo]."

Landphair: "Because the current would get you."

Lynch: "Yeah. So actually what we got here is just an elevator for boats."

The lock operator's job, opening wooden gates to equalize water levels so boats can pass, was once all muscle power. Kevin Lynch says the trickiest part of the job today, aside from dealing with floating logs and occasional dead animals, is keeping the nearly antique equipment running.

"The old Frankenstein movies, where they got the big breakers that slap in, and you see arcs flash and stuff like that," says Mr. Lynch. "That's the kind of equipment that we have."

And by law, every bit that can possibly be saved is original equipment. It's part of the charm of America's watery first superhighway: the Erie Canal.