https://en.wikipedia.org/wiki/Snoqualmie_Pass
https://wsdot.com/travel/real-time/mountainpasses/Snoqualmie
https://www.clarkconstruction.com/our-work/projects/i-90-snoqualmie-pass
https://www.atkn.com/our-work/i-90-snoqualmie-pass-east
Wow, 3 lanes each way with enough space to even become 4 lanes each way.
https://reinforcedearth.com/project/i-90-snoqualmie-pass-east-phase-1
In BC it was tough enough to go from 1 lane each way to 2 lanes each way.
https://www.youtube.com/watch?v=_m-Ilw56U8A
Its amazing to see what Washington, State & Alberta can do, simply because they aren't under BC controls & restrictions.