This is one tour that rock fans will be talking about for years to come, and if you miss it, you'll be terribly sorry. Opeth and Mastodon will be embarking on a co-headline tour this spring, which kicks off April 4 in Portland, Maine and runs through May 12 in Atlanta, Georgia. It's the first time these two titans of progressive and forward-thinking hard rock have hit the road together and it's going to be one for the ages. Ghost will serve as the opener on what has been christened the "Heritage Hunter" tour.

About the tour, Opeth frontman Mikael Åkerfeldt, with his trademark deadpan wit, stated, "We're touring North America together with Mastodon soon. Nice! One of the very few metal bands of today that I genuinely like. Good people too! Ghost are coming with us as well, and they are one of the hottest new bands to come out of Sweden in recent years, and I dig them too. I sound like an old fart, don't I? Well, I am.”

He continued, “Yet, am I right in thinking that this tour, this line up, is pretty decent? Would you all agree? Not complete s---, is it? Hope to see y'all out there! What are we playing? Not sure yet, but considering the company, maybe we'll have to pull out the big guns from time to time. In order to keep up, I mean."

Here are the dates:

4/4/2012 State Theatre Portland, ME

4/5/2012 Orpheum Theatre Boston, MA

4/6/2012 Metropolis Montreal, QC Canada

4/7/2012 Sony Center Toronto, ONT Canada

4/9/2012 Electric Factory Philadelphia, PA

4/10/2012 Wallingford, CT

4/11/2012 Roseland Ballroom New York, NY

4/13/2012 Riviera Theatre Chicago, IL

4/14/2012 The Intersection Grand Rapids, MI

4/15/2012 Stage AE Pittsburgh, PA

4/16/2012 Tennessee Theatre Knoxville, TN

4/18/2012 Diamond Ballroom Oklahoma City, OK

4/19/2012 Palladium Ballroom Dallas, TX

4/20/2012 Backstage Live San Antonio, TX

4/21/2012 Concrete Street Amphitheatre Corpus Christi, TX

4/23/2012 Fillmore Auditorium Denver, CO

4/25/2012 House of Blues Las Vegas, NV

4/26/2012 Gibson Amphitheatre @ Universal City Walk Universal City, CA

4/27/2012 Fox Theatre Oakland, CA

4/28/2012 Grand Sierra Theatre Reno, NV

4/30/2012 Paramount Theater Seattle, WA

5/1/2012 Orpheum Vancouver, BC Canada

5/3/2012 Edmonton Events Centre Edmonton, ALB Canada

5/4/2012 MacEwan Hall Calgary, ALB Canada

5/5/2012 Odeon, The Saskatoon, SAS Canada

5/6/2012 Burton Cummings Theatre Winnipeg, MAN Canada

5/9/2012 The Fillmore - Silver Spring Silver Spring, MD

5/10/2012 The Fillmore Charlotte Charlotte, NC

5/11/2012 House Of Blues N. Myrtle Beach, SC

5/12/2012 Masquerade Atlanta, GA