All vehicles, before crossing a sidewalk when emerging from a garage, alley, filling station or other place within the business district, shall come to a complete stop and shall proceed slowly and with extreme caution while crossing such sidewalk or leaving such garage, alley, filling station or other place.
As used in this section, "slowly" means such rate of speed as is reasonable and proper under the circumstances and the conditions of the street and the traffic thereon.
(1958 Code § 16.44)