If I am on a walking tour of a new city, I will carry a Leica M6 or M7 with 21, 28, and 40mm lenses. I will sometimes add a small, lightweight 75mm. If hiking through an area where I want to shoot landscapes, I have carried 24 (or 21), 28, 35, 50, and 90. If shooting close to the car, I will have an R5 or R6 with 24, 28, 35, 50, 90, 135, and 180; and probably the 60mm Macro. I may have the 35-70 zoom, which has a macro range, in place of the 35 50, and 60.
I may also have along a Nikon body with a PC lens; a fisheye; or a longer telephoto..