Strolling along a ribbon of rail may sound like a picturesque way to spend a lazy afternoon. But it's actually illegal — and it can be deadly.

Train tracks and the right-of-way surrounding them are private property owned by the railroad. Trespassing is the main cause of railroad-related deaths, according to Joyce Rose, president of Operation Lifesaver, Inc., a nonprofit rail safety education organization. “It's a stubborn safety issue. The number of fatal trespassing accidents has risen every year since 2011,” she says.

On average, 458 trespassing pedestrians die each year, often while under the influence of alcohol or drugs, according to the Federal Railroad Administration. “There are people who love railroads and trains and they're a part of the American mystique,” says Rose. “Some people think that tracks are safer than walking alongside of a highway, which just isn't true.”

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Just what makes them so dangerous to pedestrians?

Trains are heavy. In fact, they’re 12 million pounds on average, according to the Texas Department of Transportation. If the engineer sees you near the tracks, he probably won't be able to stop in time. They are much harder to brake than a car or truck, and it can take over a mile to bring one to a complete halt. “People just don't realize how long the stopping distance is for trains,” says Rose.

Even small ones take a long time to stop. A light-rail commuter train may not be as large as a freight train, but it still needs 600 feet — or two football fields — to stop, according to the Minnesota Safety Council.

“Every kind of railroad service, whether it's freight rail or passenger rail or transit, has the same risk for the driving and walking public,” says Rose. “People get distracted. You have to cross the tracks to get to the parking lot, you’re calling your husband to ask about dinner and may not realize that there's a train coming.”

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Trains are wide. Walking next to the rails is as dangerous as walking on them. Rail cars extend at least three feet beyond either side of the tracks, even more if loose straps are flapping in the wind.

“For the sake of safety, you'll want to make sure that you're at least 15 feet away from the rail,” says Rose. “Technically, people shouldn't trespass anywhere on a railroad right-of-way and that could extend for 50 feet on either side of the tracks.”

Trestles are narrow. You may be tempted to go fishing or bungee-jumping off these picturesque railway bridges. But trestles are not like bridges built for cars and trucks. There's not enough room for both you and the train. If you're caught on one when you hear that mournful whistle blow, there's nowhere to hide.

In one notable accident caught on video, a movie crew filming the Gregg Allman biopic “Midnight Rider” climbed onto a trestle. When a train appeared suddenly, an assistant camera operator died, and several other people were injured.

“The NTSB [National Transportation Safety Board] investigated and came up with some outreach recommendations for the film industry,” says Rose.

Modern trains are quiet and can hide. You'd think that something as heavy as a warship would be easy to notice. But don't count on hearing one roaring toward you from a distance.

Modern trains are relatively quiet and can sneak up on you anytime, according to the Santa Rosa Department of Public Works. Light-rail trains are even quieter, according to St. Paul Smart Trips.

For instance, traditional railroad tracks — short lengths of rail held together with large spikes — have largely been replaced with modern “continuous welded rail.” Now, several miles-worth of rails are welded together to create a single, unbroken stretch of track that makes less noise. “You don't have the clickity-clack, so you have to expect a train at any moment in any direction,” says Rose.

They're also not so easy to see, if another train is blocking your view. If you're waiting for a train to pass — even at a legal, marked intersection — don't immediately cross as soon as it's gone. A second one may be racing up from the opposite direction.

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David Arv Bragi is a freelance journalist and marketing consultant. He has been writing about health and safety issues since the 1990s and currently lives in Portland, Oregon.