This map from 2019 was compiled
using satellite and aerial imagery.
Leonardo da Vinci made this one around 1502
while stuck on the ground
When infamous Italian politician Cesare Borgia
brought Leonardo da Vinci
the guy who drew this portrait — to the city of Imola,
it was as a military engineer.
He’d already established a good military reputation
and painted several famous works.
When Leonardo was installed at Borgia’s newly acquired fort,
one of his duties was to help Borgia learn the territory.
At the time, a map like this was the standard
with the birdseye and hillside view
Mythical creatures often poped up,
not great for military operations.
The perspective also only showed some buildings,
blocking the view of other ones.
These maps could be beautiful.
But they lacked proper shape and scale
and highlighted landmarks’ beauty at the expense of clarity.
Leonardo needed to show Imola as an “ichnographic” map
— an idea that Vitruvius — a Roman engineer
and the guy who inspired this — had described.
In practice, it’s a map where everything looks like
you’re directly above whatever you show.
It gives you a clearer picture.
Look at the fort.
In Google Maps, the shadow effects change a bit,
but the fort’s perspective fundamentally stays the same.
That’s similar to a real view from far above,
where distance reduces the effects of shifting perspective.
But Leonardo didn’t have a satellite to get up that far.
His plan of Imola was a feat of symbolic imagination.
And he had to make it accurate.
Based on sketches, previous work
and the design of his Imola map,
we can guess at how Leonardo made it.
He probably used a type of disk that could measure degrees
and had a little pointer to mark the angles of streets
in relation to a stable point, usually North.
He probably used a compass to
record the orientation of the town’s surrounding walls
He did this at every turn.
which helped him accurately translate the walls onto paper.
Note the circular shape here, overlaid on the map.
To establish scale,
Leonardo also needed to measure the distance between all of these angles.
He probably paced this out by foot,
or maybe using an odometer,
with wheels that turned gears that measured distance by dropping a ball
into a bucket at set intervals.
With the angles and distance together,
he could create a plan,
hundreds of years, before anyone could check if he got it right.
The stunning map from 1551
by another Leonardo,
shows the potential Leonardo da Vinci’s method had.
All these early ichnographic maps have asterisks.
This one was spotted with its own inaccuracies and artistic flourishes,
a reflection of the scope of the project.
In turn, Leonardo’s Imola had quibbles too.
He probably used parts of previous surveys
and other artistic techniques.
It also appears that he measured the town’s walls precisely,
but took more liberties with the angles in the town’s interior.
But even with artistic license,
this remains a map of more than a fort and town.
It’s a transition from a geography of myth and perception
to one about information, drawn plainly.
It’s a map of Imola,
but in the early 1500s
it was a map of the future, too.