With nearly three months of touring behind them, the Indigo Girls [ tickets ] have added more dates to their in-progress run behind the recently released "Poseidon and the Bitter Bug."

The lengthy US trek continues Wednesday (6/10) in Vienna, VA, and--since last check--includes an additional 26 performances tacked on to the previous schedule. The duo--Emily Saliers and Amy Ray--will work its way from the East Coast to the West through late July. The outing is currently slated to wrap July 27 in Boise, ID, followed by a one-off make-up performance Sept. 17 in Asheville, NC. Details are shown below.

"Poseidon and the Bitter Bug," which surfaced in March, marks the folk rockers' 11th studio effort and their first album on their own label, IG Recordings. The two-disc set landed at No. 29 on The Billboard 200 upon its debut.

"Fans can expect an acoustic show," Saliers told LiveDaily in a recent interview. "We won't be with a band. We have Julie Wolf with us, who is a great keyboard player and vocalist. She's been a nice textural personality addition to the show. Basically, we're a couple of old ladies still doing it and still liking it."

The Grammy-winning duo has partnered with Rock for a Remedy for the spring and summer run. Concertgoers are asked to bring non-perishable food items to donate to local food banks; those who contribute four or more items will be entered into a nightly raffle to win a signed copy of "Poseidon and the Bitter Bug," along with other memorabilia.

So far, the pair has collected more than 3,000 pounds of food and enough money to allow food banks to distribute more than 27 tons of food, according to the nonprofit'swebsite.