Downtown Flagstaff is compact, walkable, and genuinely lively for a city of 75,000. The historic Route 66 corridor runs through its heart, lined with brick buildings from the early 20th century that now house independent restaurants, bars, coffee shops, outdoor gear stores, and galleries. Northern Arizona University is a few blocks south and gives the area real energy — this is not a sanitized tourist downtown.
The Amtrak station is right in the middle of it all, and the railway is still very much part of the cityscape: trains pass through multiple times a day and the whistle is part of the ambient sound. The Weatherford Hotel (1900) and the Hotel Monte Vista (1927) are the historic landmarks of the downtown strip and worth looking at even if you are not staying in them.