Friday: The Washington Post's Going Out Guide Concert Series returns with Reggae Night. The free show at the Carter Barron Amphitheatre features former Bob Marley and the Wailers guitarist Junior Marvin and his band, Junior Marvin's Force One, plus locals Ruth-Ann Brown and Ras Lidj. Seats are available on a first-come, first-served basis to the first 3,700 patrons. Gates open at 7 p.m. and music starts at 7:30.Carter Barron Amphitheatre, 4850 Colorado Ave. NW. 202-426-0486. www.nps.gov/rocr. Free.
Friday: You go to a Presidents of the United States of America show to hear them play "Lump" and "Peaches," and they most assuredly will oblige. But what happens between those three-minute nuggets of pop joy is anything but filler. The Seattle band puts on one of the most energetic, happy-go-lucky shows around, so even if you're only there to hear two songs, the full setlist will leave you smiling. Doors open at 8 p.m. 9:30 Club, 815 V St. NW (Metro: U Street). 202-265-0930. www.930.com. $25.
Friday: After months of waiting, the Bardo Beer Garden and Brewpub on Bladensburg Road NE is finally tapping its own beer. The official "World Premiere" includes some old favorites from Bardo's days in Arlington, including Marionberry Ale and Ginger Ale, plus an IPA, pale ale and stout. To make it a real party, the prices are being rolled back to Bardo's 1994 glory days: $3.45 pints and $9.91 pitchers. Doors open at 6. 1200 Bladensburg Rd. NW. www.bardo.com.au.
Friday-Saturday: The legendary comedian is at the Kennedy Center to perform three sets this weekend. Seinfeld talked to The Post's Michael O'Sullivan about life, comedy and show business before taking the stage Friday at 7 p.m and Saturday at 7 and 9:30 p.m. Kennedy Center, 2700 F St. NW. 202-467-4600. www.kennedy-center.org. $75-$150.
Friday-Aug. 16: The best thing about summer fair season is that nothing ever changes. Those same booths have been serving candy apples and funnel cakes since you were a kid, and even though you know the carnival games are designed to put you at a disadvantage, you can't help but go for that giant plush teddy bear you've always wanted. Two of the area's largest fairs, the Montgomery County Agricultural Fair and the Prince William County Fair, open this weekend. Montgomery County Fairgrounds, 16 Chestnut St., Gaithersburg. 301-926-3100. www.mcagfair.com. $10 admission, plus $10 for on-site parking; free for age 11 and younger. Prince William County Fairgrounds, 10624 Dumfries Rd., Manassas. 703-368-0173. www.pwcfair.com. $10 admission, $5 for ages 5-13 and 60 and older.
Saturday: Tiki cocktails? Check. Craft beer? Check. Water blasters? Check. The Splash Yards party at Yards Park features a giant water-gun fight, water slides, multiple pools and lawn games from 2 to 6 p.m. Bluejacket is running a tiki bar and DJs from White Ford Bronco and Rock Creek Social Club provide the tunes. Free admission is limited to those 21 and older. Third and Water streets SE. www.theyardsdc.com.
Saturday: The annual New Vintage Jazz and Wine Fest, a day of grooving and sipping sponsored by jazz chroniclers CapitalBop and the Petworth Jazz Project, returns to the Half Street Fairgrounds this weekend. The diverse lineup features soulful saxophonist Lakecia Benjamin and Soulsquad, the straight-ahead bop sound of the Elijah Jamal Balbed Quintet, and the breathtaking piano of Allyn Johnson and Sonic Sanctuary. As the music plays, artists from Art Whino paint murals, food trucks serve snacks and wine experts pour samples of 15 different varieties. A $20 ticket will get you in the door for the concert, which runs from 2 to 10 p.m.; pay $40 and you'll get admission and tastes of eight wines of your choice.