Almost 13,000 riders will make the two-day, 180-mile trek to Austin.
In the aftermath of the bombings at the Boston Marathon finish line, security at major sporting events has taken center stage.
With an event like this, security is always part of the planning process, but since Monday, organizers say they've worked closely with local law enforcement to tighten up any vulnerability.
The annual ride starts from three different locations in the Houston area and stops in La Grange tonight. It all benefits the National Multiple Sclerosis Society.
Obviously, 180 miles is a lot of ground to cover, but organizers say they feel good about the steps they've taken.
"Making sure that we have an extra heightened level of security, more security officers and their resources along the route," said Mark Neagli with the National Multiple Sclerosis Society.
They are asking cyclists to alert race staff or police if they notice anything suspicious.
"I think there's definitely a huge focus on security," participant Suruchi Srikanth said. "In the past couple days, we've gotten a lot of emails from the team about the extra precautions people are taking. And we're all going to be a lot more cautious than we would have been otherwise."
Riders also say their minds will be on the victims of the Boston bombings, saying they'll be riding in their names in addition to the cause at hand: raising money for MS research.
This year's ride is expected to raise in the neighborhood of $18 million.
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