Flight
If you are coming from Salt Lake City there is a direct 1h44m flight to Spokane (GEG) which is the closest airport to the venue. It’s about an hour drive from there to Diamond Lake. The flight is usually somewhere between $300-$400 roundtrip. There’s also an Alaska Air flight that goes through Seattle but it’s not that much cheaper if at all.
Travel Note
The drive from SLC is about 10h30m. You go up through southern Idaho then through western Montana, crossing through the pan handle of Idaho into eastern Washington.