Would an average Roman citizen know that while it was sunset in Rome, it was still a few hours before sunset in Spain?
When was the earliest that this was common knowledge?
Hi, not discouraging other responses here, but fyi, questions on the related subjects of astronomy / theory of spherical earth / determination of time of day / establishment of time zones come up here fairly often. This post from /u/jschooltiger provides a good starting point: it has links to a few more in-depth threads
This one may also be helpful