Thousands of Utahns on Monday took advantage of a free ride on FrontRunner, the just-opened commuter rail line between Ogden and Salt Lake City.

The Utah Transit Authority, which runs mass transit along the Wasatch Front, hailed its success.

The train's popularity and novelty were evident Monday afternoon, as every train was standing-room only and passengers took advantage of close quarters to get to know each other. As many as 200 passengers were forced to wait on the platform for later trains, which were also running 20 to 30 minutes late.

Midday trains had been less crowded, and many passengers were mothers with children in tow.

UTA is offering free-ride days, which continue through Wednesday, following the train's grand opening Saturday.

The premium monthly fare of $145, which includes bus and TRAX service, begins Thursday.

UTA spokeswoman Carrie Bohnsack-Ware said 500 to 600 people per train were arriving at the Salt Lake City Central Station during the Monday-morning commute. By noon, about 5,000 people had ridden the train.

"It's better than expected today," Bohnsack-Ware said.

As of 6 p.m. UTA estimated 30,000 people had ridden.

UTA estimates that once fare service begins Thursday, 5,900 riders will use FrontRunner each weekday. That number is expected to climb to 12,900 by 2020.

When UTA's light-rail line, TRAX, opened for business in Salt Lake City in 1999, officials expected 15,000 people to ride daily with an increase to 25,000 per day after a few years. Now, 40,000 to 50,000 people ride TRAX each day.

Jef Sullivan, of Clinton, normally takes the 472 express bus to work in downtown Salt Lake. But he's giving FrontRunner a month to win him over.

Sullivan was on the train at 5:55 a.m. and said the ride was pleasant and fast.

"In the long run, it could be worth it," he said. "I hate traffic."

Sullivan said he appreciates that the trains offer wi-fi access and power outlets, as well as tables for electronic devices.

Wi-fi access seemed intermittent and favoring Windows-based operating systems. Later, Apple devices had better luck — and this story was sent to the Deseret News from the train.

But during the afternoon commute home, when Sullivan left the train at the Clearfield station, he said UTA could add an extra car or two because mobs of commuters were stuck waiting 30 minutes for the next train.

The train's popularity was also evident in Layton, where the parking lot was filled to overflowing by 7 a.m., Bohnsack-Ware said, though that's likely because the train was free. Most stations have parking lot expansion plans for the future.