I am about to ask a simple question. It is not a trick question, so no reason to over-think it. The map below (like most maps) is oriented with north at the top. You might not be able to make out much detail, but that's ok, because all I want you to do is take a look at the highway shown in blue. And the question is simply this: does this highway run north-south? Or does it run east-west?
(Most recently updated 3/5/2022.) Today, Denver is served by seven different US routes (shown above), but when the US highway system was first commissioned in late 1926, only three routes went through Denver. AASHO officials acknowledged the city's importance by placing it at the junction of a major north-south route (US 85, which ran from a Canadian port of entry almost to Mexico) and a transcontinental east-west route (US 40, which connected Atlantic City NJ to the San Francisco Bay Area):