2026-02-25 Commenting on a map
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On IRC, @bss@ill.moe asked for feedback on a map. Based on what I know
about the landscape here in Switzerland, here are some basic
guidelines.

Mountains form chains unless those very rare lone mountains that are
the results of volcanoes. The most important feature of mountain
ranges are the rivers that dig the valleys.

The Jura mountains are a smaller mountain range north of the Alps.
Between the Alps and the Jura are the midlands, but even the midlands
are striated with chains of hills forming valleys containing rivers.
There are never "just hills".

Some places have regular winds from one particular direction so the
windward side is green and lush whereas the downwind side is drier.

(I don't think this is the case in Switzerland, so I don't have a
picture to illustrate it.)

Rivers form and flow from the mountains to the sea, digging valleys,
collecting other rivers, growing in size.

The Reuss flows into the Aare, then the Limmat flows into the Aare,
and eventually, further north, the Aare will flow into the Rhine.
Notice how every river joining another river is like a road, turning
to flow alongside it and then joining. No sharp turns in the water
flow.

Rivers meander. Whenever the land opens up, rivers grow longer by
adding curves. And then the curves add curves and it all turns into
marshland or swamp.

The Aare river meanders in the wide valley it finds itself in, towards
Solothurn. The plain is excellent agricultural land these days but it
was probably a dreadful marshland in the past.

Beavers build dams and flood even more land. The stagnant pools breed
bloodsucking insects and these spread diseases.

Rivers flood in spring as the snow melts and rain adds to the water
masses. The further downstream you go, the bigger the land area that
drains through this particular point and thus the more extreme the
flooding. The marshlands and swamps can compensate for a bit, but it's
still not great.

The Aare river is slow here, splits up, forms islands, and marshlands
form around it. This is near the Habsburg. That's right. The one and
only Habsburg.

Settlements will be on dry land near rivers.

Baden was built where the Limmat breaks through the Lägern. There is
rocky ground on both sides of the river. It's good for defence, it's
good against disease, and it being narrow it's good for a bridge.

Sometimes rivers can be part of the city defence.

The Aare flows around Bern, protecting it on three sides.

Lakes form where the rocky ground resists the water, forcing it
through a narrow channel.

The Reuss leaves the Vierwaldstättersee and enters a narrow valley.

Generally speaking, settlements should be nearer to valuable
locations. That means: lakes, rivers, estuaries. Add a settlement to
every river delta, every lake, and along every river that can be
navigated. If there is no settlement, it needs an explanation. The
biggest settlements are at the river delta because of trade along the
coast.

Bigger lakes have multiple towns. One of them is going to dominate the
lake, usually where the water leaves the lake. Often the name of the
lake and the name of the dominating city are the same: Thun/Thunersee,
Biel/Bielersee, Zürich/Zürisee, Murten/Murtensee, Genf/Genfersee.
Sometimes there's a story: The Vierwaldstättersee is not the
Luzernersee because it's very large and many cantons border it. The
Neuenburgersee is not the Yverdonersee because Neuenburg/Neuchâtel is
a canton in its own right whereas Yverdon is in the canton of Waadt
dominated by Lausanne.

Thun is dominating the lake of the same name. Spiez is a nice small
town, for sure. But Thun rules the lake.

The smaller settlements along the river are important because upriver
travel is slow. Ships can sail upriver if the river is large and slow
but as it narrows and speeds up, rowing, poling, and pulling by
animals (on special roads next to the river) is used to get ships
upriver.

Not every place along a river is great, but a river offers a toll
tower with which to force ships to pay; a toll bridge with which to
force ground traffic to pay; a harbour for ships; inns for the crews;
a market for the wares.

A place without sweet water needs to build cisterns, canals and
aqueducts. It's expensive and you only do it if the place is
important. Usually these are fortified places on hilltops. Thus, they
are indicative of a border. This means that there must be good arable
land on either side, or at least on one side with steppes potential
nomad herders and raiders on the other side. Without anything to
protect, there are no border towns.

The map screenshots are from the digital Dufour map, finished in
1865. The maps of Switzerland are all available online. Notice the
option to "Journey through time". The Dufour map was a project by the
Swiss nation state to constitute a geo-body, which is why all the
lands beyond the border are not shown. You can get copies from
Wikimedia Commons.

There is an app, too.

#Maps #RPG