Prog-metal veterans TOOL continue to add pieces to their emerging summer tour schedule, with the latest additions including a headlining appearance at Chicago's Lollapalooza.

The band, which has been on something of a hiatus since its 2006-2007 world tour following the group's most recent studio album, "10,000 Days," currently shows five live dates on its calendar, kicking off July 18 in Commerce City, CO, with an appearance at the Mile High Music Festival. Before Tool's headlining appearance at the Aug. 7-9 Lollapalooza, the band will also make stops in Salt Lake City (7/19) and Grand Prairie, TX (7/25), as well as an Aug. 1 slot at New Jersey's All Points West festival.

Released in April of 2006, "10,000 Days" debuted at the top of The Billboard 200 chart after moving about 564,000 copies during its first week in stores, and also earned the band two Grammy nominations, including Best Hard Rock Performance for the song "Vicarious."

In February, frontman Maynard James Keenan told MTV.com that the band would start writing material for its fifth studio album "right away," but didn't offer a timetable for the set.

"The music always comes first," Keenan said. "We all get in a room, shut out all the extra noises from the other people and what goes on outside the room and just focus on the four of us, where we are that day. And then we just start making sounds."- livedaily.com