The Bridge brothers are about to get rocked into the ground by musicians nearly twice their age.

When Brookstock XVIII begins Saturday night, brothers Nick and Tyler Bridge will ready-up their own Bridge Band and also provide backing guitar, bass, drums and vocals for pretty much every other performer, all of whom are Brookhaven High graduates from the late 1960s within a year or two of their 70th birthdays. The Bridges will use their youthful energy — Tyler is a fresh 40 — to back up the seasoned rockers on around 50 songs for almost six solid hours.

“I learn from all these guys and I’m hoping I’m still able to rock like they do when I’m their age,” Tyler Bridge said. “Some of them rock harder than I do now.”

Brookstock started in 2000 as a reunion of The Brutes, a high school band started by Brookstock organizer Don Jacobs and the late Virgil Brawley. The show was part of a reunion for the Class of 1968, but the event and its guests have grown beyond one show, or one class.

Now, Brookstock stretches over three nights and four events and draws local music-lovers of all ages.

“Most of us have known each other, more or less, just from being from Brookhaven High or living in Brookhaven. But, at the same time, half the people who come today I don’t know,” Jacobs said. “Brookstock is pretty much music from the 60s and 70s with a mix of blues, but anybody who might have an interest in hearing some live music is welcome. It’s open to anyone and everyone, all ages.”

The 18th annual Brookstock performances begin today with singer/songwriter night at Recess 101. Shaw Furlow, Tommy McClymont, Don Jacobs, Greg Smith and Sophie Smith will perform original music in an “unplugged” atmosphere.

Doors open at 6 p.m. and music begins at 7 p.m. Admission is free, and guests need to bring their own refreshments.

The show goes on Friday night with Brookstock Too at The Haven, where youth bands The Genius Edition and The Upside will perform. Doors open at 6 p.m. and music begins at 7 p.m. Admission is $10.

The Brookstock Breakfast Club meets Saturday at 9 a.m. at Chism’s Diner. Anyone who wants to hang out with the band is invited.

The big show — Brookstock itself — will be held Saturday night at the Brookhaven Building on Beltline Drive. Doors open at 5 p.m. and music begins at 6:30 p.m. The event will be catered, but visitors also need to bring their own refreshments, just in case the caterer’s aren’t strong enough. Admission is $10.

This year’s Brookstock is dedicated to Brawley, who died at 69 on June 22. He was a veteran, horse-trainer, sound engineer, recognized guitarist and an important piece of the Brookstock machinery.

“He’s not the first one we’ve lost, but having been a founding member of The Brutes, it’s going to be strange not having him there,” Jacobs said.

Jacobs said organizing the growing Brookstock events becomes more difficult each year, but he believes 18 years of performances have helped grow Brookhaven’s emerging local music scene and he plans to keep it going.

“It’s fun to get together with all the musicians who have played together over the years, fun to see these familiar and unfamiliar faces,” he said. “Once Brookstock time rolls around every year, it’s worth it.”