If it's a main interstate, then I'll call it "I-[x]". So I drive on I-5 or I-90. If it's a spur, then I just use the number. From Redmond, I would get on 405

If it's a main interstate, then I'll call it "I-[x]". So I drive on I-5 or I-90. If it's a spur, then I just use the number. From Redmond, I would get on 405 to go to Bellevue. When I drive from Sunnyvale to Palo Alto, it is usually fastest to take 101 unless it's rush hour.