On the road together for an extended period for the first time since 2009, Willie Nelson, 91, and Bob Dylan, 83, each brought the house down Wednesday night at the Hollywood Bowl, where the two living legends performed separately as part of this summer’s traveling Outlaw Music Festival.

Here are 10 highlights from the sold-out show:

1. Nelson, who launched the annual Outlaw tour in 2016, was forced to pull out of the first few dates of this year’s edition due to illness. Here, though, he seemed in fine fettle as he shuffled onto a bare stage with his six-piece band, took a seat next to his son Micah and opened his hour-long set with a frisky rendition of “Whiskey River” as he’s done so many times before.

2. Nelson’s other son, Lukas, was missing from his usual spot in his dad’s ensemble on Wednesday. Yet Nelson had a handful of unannounced guests in John Densmore of the Doors, who manned various percussion “doohickeys,” as the singer put it, throughout the gig; Amanda Shires, who played fiddle in a spirited “I’ll Fly Away”; and Lily Meola, a former “America’s Got Talent” contestant who joined Nelson for a smoldering take on their “Will You Remember Mine.”

3. “Angel Flying Too Close to the Ground” sounded like a piece of eternal wisdom when Nelson wrote and recorded it for 1980’s “Honeysuckle Rose.” Nearly half a century later, the country-jazz ballad is still a showstopper; indeed, if anything, the song’s beauty has only deepened as Nelson somehow continues to find new ways to twist its winding vocal melody. A+ guitar solo too.

4. This longtime progressive activist didn’t say anything election-related from the stage, though it seemed notable that in a crowd-pleasing set long on hits — “On the Road Again,” “Always on My Mind,” “Mammas Don’t Let Your Babies Grow Up to Be Cowboys” — one new tune Nelson opted to play was the title track from this year’s “The Border” LP: a stark depiction of the moral complexities at work in a place often reduced to a political cartoon.

5. Memories of the Dylan-goes-electric days have been in the wind lately thanks to the just-released trailer for James Mangold’s upcoming biopic starring Timothée Chalamet. Yet here Dylan reached back to before that epochal shift with loving covers of late-’50s classics like Chuck Berry’s “Little Queenie” and the Fleetwoods’ “Mr. Blue,” the latter of which felt lighter than air.

6. Then again, Dylan’s snarling take on the delightfully nasty “Ballad of a Thin Man” — which he performed, like most of Wednesday’s set, in a wide-legged stance behind a grand piano, his shirt open nearly to his belly button — suggested he can still find fresh irritation in the misunderstandings of the mid-’60s.

7. Longtime pals — and onetime “We Are the World” collaborators! — Dylan and Nelson never teamed up at the Bowl, though Dylan did invite Nelson’s harmonica player, Mickey Raphael, to sit in for a very lovely “Simple Twist of Fate.”

8. In addition to the two headliners, the Outlaw tour features a third veteran of American roots music in John Mellencamp, whose fervent, if somewhat parched, readings of “Small Town” and “Pink Houses” on Wednesday made you ponder how radically ideas about the heartland have changed over the last four decades.

9. Mellencamp’s way of boiling down the message of his song “Longest Days”: “Stop giving a f— about stuff that’s not f—worthy.”

10. A young face among all the grizzled visages, Brittney Spencer — who got a boost this year when Beyoncé featured her on “Cowboy Carter” — opened the concert with a sly and buoyant performance that climaxed with a mashup of Garth Brooks’ “Friends in Low Places” and her own “I Got Time.”