DIRECTIONS: Two great ports now sit inland, with fields where the ships were. Work out why.
Rivers drop their mud where they slow down: at the sea, where the harbor is.
The port
What it was
What happened
Ephesus (Turkey)
one of the great ports of the ancient Mediterranean, with a harbor at the heart of the city
the river silted the harbor up over centuries. The ruins are now some way from the sea, with flat farmland in between
Bruges (Belgium)
one of the richest trading cities in medieval Europe, reached from the sea by a tidal inlet
the inlet silted and the ships could no longer get in. Antwerp, which they could reach, took the trade
Nobody could have out-worked this. A port is not a decision, it is a depth of water, and when the water stops being deep enough the ships go somewhere else — not out of preference but because they physically cannot arrive.
Bruges is the sharper case, because the trade did not disappear. It moved down the coast to Antwerp, which is what a place losing its position looks like from the outside: somebody else is suddenly doing well.
The obvious next move is to measure it. How far is Ephesus from the sea now? This shelf cannot tell you, and the reason is worth more than the number.
The coastlines in these packs are drawn for maps of the world. They are made of points a long way apart — enough to draw Turkey correctly on a page, nowhere near enough to answer a question about a few kilometers. Asking them how far Ephesus is from the water gives an answer that is wrong by tens of kilometers, and it gives it confidently, which is worse.
social-09-world-geography sheet 20 is about exactly this: how long a coastline is depends entirely on how closely you measure it, and there is no final answer.
Say what kind of map you would need to answer "how far is Ephesus from the sea now" properly — and what you would need as well as a map.
The Harbor Filled In — Why You Cannot Check This Here
Why it stopped mattering · Page 2 of 2
A confidently wrong number is worse than no number. Say why.
Silting takes centuries, so nobody alive ever saw it happen. Say what that means about whether anyone could have noticed in time — and what they might have done.