Colorado has four area codes, but only 303 can lay claim to being the first (it was put into place in 1947), the oldest by far and the most palindromic. That OG vibe also gives it the most cachet, which is why people in Denver and its suburbs, which is where most of the 303 numbers are distributed, like to name their restaurants, auto shops, stores, publications and products after those magic digits.
When it comes to beer, Station 26 Brewing scored a major victory two years ago for all things local when it secured the trademark "statement of use" rights to 303 for beer and brewery-related products.