They're aboard because they love trains: the pilot from New Orleans, the computer consultant from New Jersey, the retired tax lawyer from Florida, the computer accounting consultant from Queens and his mother, the retired  corporate executive, the computer scientist from Florida's Space Coast.

For the past decade, these one-time strangers — all train geeks — have made several cross-country trips together on Amtrak. They talk trains and gossip along the way as an extended, traveling family of sorts. By the end of their most recent trip, in July, they would lose a member.

They came together through two train fan websites, discussions about rail travel leading to group trips on a mode of transportation that, though well past its heyday, still accounts for almost 32 million annual trips.

Chris Wyatt, a 35-year-old pilot from New Orleans, joined the online forums more than a decade ago and went on his first trips with the train groups a short time later.

"It's nice to talk to someone who shares my same hobby," he says. "Otherwise, I would be taking these trips by myself. I've made lifelong friendships."

For many train group members, meeting one another is strange after interacting online.

"Some people who had a strong online personality had, in person, a very timid personality," Penny Jacobs said.

On their regular train trips, New Jersey computer consultant Kevin Korell, 58, serves as informal recording secretary, logging the exact arrival and departure times at stations.

Jacobs, a 65-year-old Florida attorney, is known for walking up and down the length of the trains, an in-transit substitute for her yoga classes.

The sleeping car of fellow Floridian Dick McCauley, a retired corporate executive, often serves as a social hub before dinner because, as a disabled-accessible room, it has more space than other compartments.

Jishnu Mukerji, a retired computer scientist from Melbourne, Fla., just likes to read and watch the scenery.

Alan Burden, a 57-year-old computer accounting consultant from Queens, New York, always listened to radio communications on his scanner and could answer any of the travelers' questions if a train unexpectedly stopped or backed up.

Burden was one of the first members of the Amtrak Unlimited website and often planned the gatherings. He loved helping strangers on the street figure out New York's transit system. His thorough knowledge of railroads earned him a devoted online following.

"His answers were always detailed and eloquently written," said Anthony Rizos, who created the site in 1997. Rizos, now an airline executive, had fallen in love with trains during a West Coast trip and launched the forum as a precocious 10-year-old.

Amtrak Unlimited members hold annual three-day get-togethers, dubbed The Gathering, riding local transit in different cities and topping it off with a big dinner for three dozen or so members.

The smaller On Track On Line, also launched in the 1990s, attracts hardcore train lovers more familiar with railroad operations. Its members take two trips a year: a long weekend usually in January and a longer trip — a week or more — in the summer, known  as Railfest.

Korell, who collected train schedules in the days before the internet allowed him to put trips together online, meticulously plans Railfest each year and emails down-to-the-minute train schedules to his 10 or so fellow travelers.

"I like to make these fantasy trips," said Korell, who gravitates toward cities with newly opened rail lines. "I put these fantasy trips together and then decide if this will be good for the group."

This summer, the train aficionados traveled to New Orleans and Houston. Wyatt and Burden and his mother, Grace, started in New York and picked up the others in Washington.

The group had gathered in the dining car on the Crescent line leg to New Orleans, and Burden hadn't shown up.

Jacobs texted Burden in his sleeping car to ask whether he was coming. He texted back: "Quite possibly having a heart attack."

"Really?" Jacobs texted. "No joke," Burden replied.

Jacobs said she immediately ran to a train attendant, who notified a conductor. A dining room attendant who had trained as a paramedic rushed to Burden's room. The conductor stopped the train at a crossing in rural Alabama, where paramedics transported Burden to a nearby hospital. He died there.

Railfest members decided that Burden wouldn't want the trip interrupted, so more somber than usual, they continued to New Orleans and Houston.

A month later, Burden's train friends from across the country gathered at a memorial service, in Pennsylvania. Most traveled by rail.