On the eve of their tour kick-off, progressive alt-rockers The Mars Volta [ tickets ] have expanded the US headlining outing behind their recently released new album, "Octahedron."

The Texas-born, Mexico-based group begins the summer and fall excursion tomorrow (8/29) with an appearance at San Francisco's Outside Lands Festival, followed by a handful of West Coast stops before heading east. Since last check, seven shows have been added, including gigs in Toronto (10/4) and Montreal (10/5) and a trio of shows on the East Coast. Details are shown below.

"Octahedron," the band's fifth studio set, hit shelves in June and debuted at No. 12 on The Billboard 200. The new effort follows last year's "Bedlam in Goliath," which featured the Grammy Award-winning single "Wax Simulacra."

Before recording the new album last year, frontman Omar Rodriquez-Lopez pared the band down to a six-piece lineup, relieving guitarist Paul Hinojos and saxophonist/percussionist Adrian Terrazas-Gonzalez of band duties, according to The Mars Volta's website.