Yeah, it always sticks in my mind that the time it takes for light to reach the top of the Eiffel tower from the ground is measured in nanoseconds. Maybe that came from a Grace Hopper talk?
Microseconds even! Light travels about 0.3 meter in a nanosecond, and the Eiffel tower has a height of ~300 meter, so it takes about a microsecond for light to get from the ground to the top.