The southern façade is dominated in the middle by an imposing, crenellated 22-metre-high keep with porch. It shows real quality construction (large stonework) and a sure sense of taste in the ornamentation (yellow and white stones, crowned arches, finely-worked arrow slits, etc) .
The sculpted crests on the keep and above the windows represent the seigniorial families who succeeded each other at Gombervaux.
Only three of the original four towers remain; the north-western one has disappeared, and the north-eastern one partly collapsed during the 1952-53 winter.
Originally, these towers, almost as high as the keep, were topped with conical, tiled roofs (with the exception of the north-western tower, covered in slate).
One of the jewels of the chateau is the great hall of the south-western residence, recently protected by a vast roof. In the centre is a great chimney whose abutments rest on trapezoidal supports, in the gothic style. It is probably in this chimney that Taillevent roasted boars, peacocks and partridges at the banquet served to Charles V in 1367. The vault of one of the two windows framing the chimney is decorated with little flowers painted onto the stone.