Where Does The "X" Come From In The Airport's Name "PDX"-Interesting Story

I've always wondered how PDX Airport got its name - PDX. Just where did the "X" come from and why? I came across this story from Devon Haskins - KGW Staff and I had to share. It really is an interesting story. I never knew Portland's first airport was located on Swan Island, did you? Check out this story and your questions will be answered and then some. Again, thank you and courtesy Devon Haskins KGW.com.