One of six major league baseball stadiums with some form of retractable roof, Miller Park is the only place with a diamond-shaped dome that retracts neatly to reveal the grassy field underneath; all the others involve boring square-shaped configurations.
Opening the roof at Miller Park happens slowly, using forces of Sisyphean determination, as a squadron of 10 electric motors called “bogeys” slowly part the roof using 60 horsepower engines, about the oomph of a medium- sized motorcycle. The decision to open or close the roof due to inclement weather rests solely with the Brewers themselves.
Fun Facts About Miller Park’s Retractable Roof
1) Each panel is moved by two tractor-like engines (aka “bogeys”) at a speed of half a mile an hour.
2) The tallest arch extends 30 stories in the air.
3) Inside the stadium, the ceiling rises some 200 feet above second base.
4) Even though the roof covers more than 10.5 acres and is made of 12,000 tons of steel, it takes only about 10 minutes to completely open or close.
5) Seven interlocking panels stretch some 600 feet, from a position high above home plate to a beam over the outfield. Each of the three largest covers approximately the same surface area as the Bradley Center’s roof.
6) The Bogeys move around a semi-circular track like little trains.
7) While the stadium’s lid remains closed during the off-season, natural grass can still grow thanks to these stories-high windows.