Half-timbering technique was a popular method to build houses in medieval and early modern times in Northern Europe (Denmark, England, Scotland, Germany / Prussia, parts of France and Switzerland). Houses were constructed by first installing timber frames. The space between polls and planks was later filled in with other building materials like stone, bricks, etc. In medieval cities to provide more housing space in houses built alongside narrow streets, many houses were constructed with overhangs of upper floors over the ground floor (called jetties).
The streets of historic towns in Northern France are a mixture of different architecture styles, sometimes well-preserved from the past, occasionally rebuilt after fires or war damage. On pictures above you can see three main characteristics: grey sandstone bricks, slate roofs that sometimes cover also part of facades at upper floors and half-timbered walls with timber frames painted mostly in blue, red and green.