If you’re visiting Southern California, taking the train from Los Angeles to San Diego makes sense — on one level. You’ll see the area’s iconic beaches, strawberry fields and historic railroad stations without having to worry about freeway traffic.

On another level, it doesn’t make any sense at all.

Round-trip tickets for my family of four on the Pacific Surfliner cost $248, and the trip takes about an hour longer than driving (assuming the train is on time). As much as I wanted to reduce our carbon footprint, a tank of gas for our Honda CRV costs only $60. Plus, we weren’t limited by Amtrak’s schedules.

Still, more travelers are asking a question they haven’t for years, perhaps even for generations: Should I take the train or drive? It’s not always as clear-cut as it was for me. A few simple questions can help you determine whether the train is the right choice. Taking the train may not always make sense, but it might more often than you think.

Why are we having this discussion now? There is a deepening collective realization that travel — at least the way it has been practiced in recent decades — is harmful to the planet. The flight-shaming movement denounces the environmental damage caused by air travel; the slow travel movement emphasizes longer stays; and the “micro-cation” trend speaks to the increasing popularity of vacationing closer to home.

Amtrak is ready. In fiscal 2018, Amtrak transported 31.7 million passengers in North America. Preliminary estimates suggest its ridership grew by about 1 million passengers in fiscal 2019. The rail carrier says it’s a greener way to travel — 47 percent more energy-efficient than travel by car and 33 percent more energy-efficient than by domestic airline. By the way, if you want a birds-eye view of Amtrak’s availability, check out Amtrak’s Track Your Train website.

“Operating an environmentally efficient, safe and fiscally responsible business is essential for future growth,” says Roger Harris, Amtrak’s executive vice president.

So should you take the train? Ask yourself these questions:

Where are you headed? Some countries have a reputation for first-rate rail systems. “I found the trains in Germany and Switzerland are clean, efficient and on schedule,” says Nicholas Wolaver, a communications consultant from Atlanta who travels frequently in Europe. “A journey from Munich to Lausanne, for instance, took about a day.” He made a few stops and explored several cities along the way.

Is the ride a destination unto itself? “Take the train when it’s a must-do experience,” says Kristine Thorndyke, a teacher based in Shanghai. That would include a trip on such a famously scenic route as the one traversed by the Coastal Classic between Anchorage and Seward in Alaska or the Glacier Express between Zermatt and St. Moritz in Switzerland — in other words, the rail equivalent of crossing the Atlantic on the Queen Elizabeth 2.

How’s the traffic? One of the best reasons to take a train, at least in the United States, is to avoid road congestion in metropolitan areas. “I usually choose the train, especially when I am in New York, to avoid traffic,” says Melanie DiSalvo, an apparel supply chain consultant based in New York. The Acela from Washington to New York takes just 2 hours 35 minutes on average — almost two hours less than driving.

What about other delays? In Europe, you can use a simple calculation to decide whether to take the train or fly, says Nadia Elizabeth, a U.K.-based travel blogger and frequent train rider in Europe. “If the train takes less than five hours, it’s almost always better than flying because that’s the minimum time you’ll spend mucking about on even the shortest intra-Europe flight.” You have to factor in travel time to the airport, security delays and other airport hassles. And remember, unlike an airplane, the train usually takes you right to the center of town.

Are there any hidden fees? Renting a car may seem inexpensive, but other factors associated with travel by car can affect your trip. Consider what happened to Stephen Guerriero, a middle school teacher from Needham, Mass., on a recent trip to Europe. “We incurred a 150 euro penalty in Slovenia for not understanding their weird tolling system,” Guerriero says. “And gas is crazy expensive.” In Italy, he suffered more toll-related penalties, and in Spain, he got two speeding tickets whose cost was increased further by the rental company’s processing fees.

When I visited California recently, I decided to leave the car at home and boarded the morning Pacific Surfliner for San Diego. Construction on the tracks caused a two-hour delay. Once underway, the kids and I spent our time staring out the window and watching Southern California go by — beaches, small towns, big cities, freeways. The Surfliner was almost empty, but there were plenty of cars on the freeway. We were happy to avoid them, and maybe lessen our carbon footprint a little, too.

We’re spending 2020 in Europe, and we’ll be buying a Eurail pass to get around. If we need a car for a few days, we’ll rent one from an agency such as Auto Europe. For us, the question of taking the train vs. driving will default to “train” for the next year. I’ll let you know how that goes.

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