In addition to being perhaps his greatest work, Mozart's Requiem is also a sublime "gateway" opus for anyone unfamiliar with this incredible composer's works. It is emotionally tremendous, orchestrally awe-inspiring, and chorally haunting. If you love music (of any kind) you will love the Requiem.
Performances run Saturday, April 6 - Monday, April 8 at Portland's Arlene Schnitzer Concert Hall, and students can store discounted tickets. (Recent acoustic enhancement at the Schnitz mean that there's not a bad seat in the house!)
More info HERE:
https://www.orsymphony.org/concerts-tickets/2324/mozarts-requiem/
P.S. While in Vienna, you can visit Mozart's apartment. And while in Salzburg, you can visit his birth-house.