This year’s Northwest Folklife Festival, which is expected to attract about 250,000 visitors, opens Friday at Seattle Center for four days of live performances.

Admission is free, but Folklife welcomes donations of $10 a day for individuals and $20 a day for families.

This year’s cultural focus is the centennial of Seattle’s first world’s fair, the Alaska-Yukon-Pacific Exposition, which drew 4 million visitors to Seattle in 1909. Read Don Duncan’s story about the A-Y-P Exposition in the Seattle Times.

Some of the same ethnic communities represented 100 years ago will be honored at Northwest Folklife, among them Scandinavians, Japanese, Chinese, Hawaiians, Filipinos and native Alaskans.

Mayor Greg Nickels’ official A-Y-P Centennial kickoff is Saturday at 3 p.m. at the Mural Stage. Activities include parades by the Mak Fai Washington Kung Fu Lion Dancers and Skandia Allspel, a Hyperbolic Singers performance of “Seattle, The Peerless City” (adopted in 1909 as Seattle’s official song), and music by the Ballard Sedentary Sousa Band (so named because the band doesn’t march).

Here’s a link to the complete Northwest Folklife schedule.