European cities are a mix of unplanned and thoroughly planned. High Middle Ages in more developed places already had some municipal bureaucracy and planning offices.
Take a look at Prague, for example. [0]
There is a chaotic maze of medieval streets in the Old Town (around the Astronomical Clock). But the New Town to the southeast, which was founded in 1348, is already much more regular; the king who founded it had a certain vision and the street grid reflects that vision. Interestingly, a mid 14-th century grid was able to accomodate some degree of car traffic of our modern era.
In case of Kraków [1], there isn't any unplanned corner of the city left, the grid in the Old Town is perfectly regular. This was designed around 1260, so a pretty old grid, but a planned city nonetheless.
Take a look at Prague, for example. [0]
There is a chaotic maze of medieval streets in the Old Town (around the Astronomical Clock). But the New Town to the southeast, which was founded in 1348, is already much more regular; the king who founded it had a certain vision and the street grid reflects that vision. Interestingly, a mid 14-th century grid was able to accomodate some degree of car traffic of our modern era.
In case of Kraków [1], there isn't any unplanned corner of the city left, the grid in the Old Town is perfectly regular. This was designed around 1260, so a pretty old grid, but a planned city nonetheless.
[0] https://goo.gl/maps/1cz13fsr5tPP52AF9
[1] https://goo.gl/maps/CRkLPM9i7MRVH1aK8