system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Before aviation, how was it possible to make such detailed maps of the world?

Before we could see the world from above, how were worldmaps, like those used by the East India Company and the Dutch VOC made? How did they know the shape of the continents?
gpt
The maps weren't all that accurate, but they were made by using a ship to follow coastlines, plotting the direction and length of time taken to reach a certain point, all while staying the same distance from the shore. This allowed for maps that, while lacking in detail, showed enough of the area to be useful for navigation.