Here’s what the website had to say:
Seattle Mariners/ San Diego Padres, Peoria Sports Complex
Built in 1994, Peoria Sports Complex was the first MLB spring training facility built for two teams. Located in Peoria, Arizona, it is one of the larger spring training facilities with a capacity of 12,000.
One notable interesting tidbit about the complex: It was designed as a perfect circle with the field being in the middle, and everything revolving around the field. So no matter what activities you may want to partake in, they all take place surround the field so you always know where you are.
Fans often bring blankets and lawn chairs and enjoy the grass seating in the outfield. It is also a great spot for children as they can join the “Kids Club” and receive 10 free game tickets, batting cage opportunities and direct access to select players.
Other Spring Training sites making the cut were the Los Angeles Dodgers and Chicago White Sox Camelback Ranch and San Francisco Giants Scottsdale Stadium in Arizona, as well as the Atlanta Braves Champion Stadium, Tampa Bay Rays Charlotte Sports Park, Minnesota Twins Hammond Stadium, New York Yankees Steinbrenner Field and the Philadelphia Phillies Bright House Field, all in Florida.
By the way, Mariners pitchers and catchers report to Peoria on February 19, position players will arrive on the 24, with the first full squad workout scheduled for February 25. Games start on March 2. Tickets are available at Mariners.com/Tickets.