This year, the Arlington County Fair had something new to offer: an opening day parade.

The 39th annual fair, themed “Summer Nights and Lights,” opened yesterday. An hour after opening, the parade processed down S. Highland and 2nd Streets. Participants included local Boy and Girl Scout troops, local businesses and several local dancing groups.

Arlington dance group Alma Boliviana, founded in 1991, performed a Bolivian folkloric dance in the 90 degree heat as part of the opening procession.

Group member Gabriela Grajeda said Alma Boliviana, which marched in the Macy’s Thanksgiving Day Parade in 2011, was excited when Arlington County invited them to be part of the fair’s festivities.

“It was great — we definitely want to come back next year,” Grajeda said. “And now we’re going to go enjoy the fair!”

The fair will continue through Sunday (Aug. 9). Notable upcoming events include performances by The Harlem Wizards and outdoor concerts on Saturday and Sunday, as well as daily pony rides, milking demos and piglet races, where four week-old piglets run around a small dirt track to receive a treat.

Piglet racing proprietors Rick Signor and James Caruso were enthusiastic about the fair.

“This is a great one,” Caruso said. “Everyone’s been so receptive, and the crowds are great — not just the kids, the adults are having fun too.”

A full schedule of events and list of vendors can be found on the fair’s website.