This week I’m looking at stairs. I realized the other day that I climb stairs a lot; when you have pneumonia and crossing the room makes you breathless, you become very aware of stairs.
These are the stairs at my dentist’s office. I don’t know if it’s carpet cleaner or what, but there is a very distinct peppery smell as you enter this building. I notice it every time. 
His office is at the top, immediately on the right.