The Les Schwab Amphitheater is celebrating 20 years of live music and is offering a limited release of $20 flat rate tickets to 20 different shows for the upcoming season. The tickets will all go on sale starting at 10 am on Saturday at the ticket mill in the Old Mill District, and will need to be purchased in person. There will be a limit of two tickets per person at that price. 20 of the tickets at the special $20 price will be sold per show.