What does a city smell like at 5am?

I was walking back from the station last week, just after the night shift ended, and the air smelled like wet concrete and old coffee, but also something else—like the city exhaling. Not clean, not dirty, just… tired. I’ve been thinking about how language fails us when we try to name that moment. We say 'early morning,' but that’s not it. It’s the in-between. What do you think? What does your city smell like when no one’s watching?