Although the shape of this Bay on the coastline of the Adriatic Sea makes it look like a classic Fjord, a valley where a glacier once sat that was flooded when sea levels rose…there’s something slightly different about it. Most fjords actually head out to sea and open where the glaciers reached the coastline, but the Gulf of Kotor does not.
The Gulf of Kotor is one of 4 distinct gulfs, each fed by water from the Adriatic. Water enters a gap called the Kumbor Strait and floods an area that is roughly parallel to the coast, creating two gulfs named the gulfs of Herceg Novi and Tiva. Water then flows from those gulfs through another thin gap called the Verige Strait where it floods another area containing the Gulf of Kotor and the Gulf of Risan.
These areas are flooded valleys and may even briefly have had glaciers in them, but they owe their origin instead to erosion. The rocks in the area have been folded, creating highlands where the rocks have been bent upwards and lowlands where the rocks have been bent downwards. On the slope in the distance note how you can even see that specific beds run parallel to the ridge – expressing how the beds have been folded. The rocks themselves are limestones, so they also dissolve fairly easily in water, allowing cracks and caves to form in a classic pattern called Karst.
This setup created a situation with ridges and valleys running roughly parallel to the coastline and thin gaps in-between the ridges. The valleys were low enough in elevation to be below modern day sea level, although when glaciers were present sea level was over 100 meters lower and these areas were far above the ocean.
When the massive ice sheets melted, sea level rose again and found the cracks in-between those ridges. Water rushed in through the Kumbor Strait, flooding the first two gulfs. It then found the Verige strait as another gap that let it access yet another valley, where the water then flooded the Gulfs of Kotor and Risan.
These valleys therefore look a lot like fjords but their story is different. Their origin lies in the folding of rocks and the cutting down of rivers rather than the work of massive ice tongues. Because they’re protected from the open ocean but still have access, these Gulfs have been locations of commerce and even religious pilgrimage for millennia.