There’s a sunken courtyard near the office where I work. It’s shaded on three sides by an office building, a hotel, and a parking structure. Trees soften the sunlight that does make it through. Three steps lead down from the edge to the brick floor, with a smattering of concrete benches and planters.
One day last winter, a rainstorm flooded the courtyard. Not very deep, maybe an inch or so (if that). Just enough to turn the bricks into a mirror, which really struck me as bizarre.