The rotating cast of guest acts will include Medeski, Martin & Wood, Toots & The Maytals, Jurassic 5, Galactic, G. Love & Special Sauce, The Black Keys, Gomez, Ray Lamontagne, and Donavon Frankenreiter.

Most guests will stay on board for at least a week, with Anastasio and Harper headlining all dates. Organizers say a total of 20 to 25 guest acts will eventually be announced.

The tour begins June 16 in Camden, N.J., and will cover amphitheatres in the East Coast and South extensively before heading for Canada and the rest of the U.S.

The outing will wrap July 31 at the Gorge Amphitheatre in George, Wa.

Tickets look to be the same price for all dates: $32.50 for lawn seats and $47.50 for reserved seating. Ducats for select shows were to become available via Internet presale April 29 at zoomatour.com.