Those summer performances at Wolf Trap National Park for the Performing Arts paid off in a big way in 2011.

Verdine White, Ralph Johnson and Philip Bailey of Earth Wind & Fire keep the grooves coming in New Orleans but also helped Wolf Trap have a super summer. (Rick Diamond/GETTY IMAGES)

Familiarity is one key to Wolf Trap’s success. Among the most popular programs in 2011 were Garrison Keillor, Bill Cosby and the National Symphony’s accompaniment to the classic film “Casablanca.”

Officials at Wolf Trap reported the following shows were its best-sellers.

The live broadcast of “A Prairie Home Companion” with Garrison Keillor. (video of Keillor above)

Bill Cosby

RAIN -A Tribute to the Beatles

Daryl Hall & John Oates

Earth, Wind & Fire

Goo Goo Dolls with Michelle Branch and Parachute

National Symphony Orchestra--Casablanca

Dolly Parton

Alison Krauss & Union Station

Steve Miller Band