The upcoming "Walking With Dinosaurs: The Arena Spectacular" event at the Yakima Valley SunDome is billed as the biggest show to ever play Yakima.

Now, officially, it is.

SunDome officials announced Tuesday that "Walking With Dinosaurs," which comes to town the end of this month, is the highest grossing ticketed event in the venue's 19-year history.

And it isn't even sold out.

Tickets are still available to the five previously announced performances, plus tickets to two added shows -- 7 p.m. April 23 and 3 p.m. April 24 -- go on sale at noon today.

"Walking With Dinosaurs: The Arena Spectacular" is a mix of animatronics, puppetry, science and theater magic that brings to life 15 full-size dinosaurs, including a 36-foot tall Brachiosaurus and a Tyrannosaurus Rex that's 18 feet tall at the shoulder. It's based on the Emmy Award-winning BBC television series "Walking With Dinosaurs," originally broadcast in 1999.

Tickets for all shows -- which are now 7 p.m. April 23; 3 p.m. and 7 p.m. April 24; 11 a.m., 3 p.m. and 7 p.m. April 25; 1 p.m. and 5 p.m. April 26 -- are available through TicketsWest, 800-325-7328, www.ticketswest.com, or the State Fair ticket office, 509-248-7160. Tickets range in price from $19.50 to $47.50.