The oldest cellar of the estate dates back to first construction of the fortress. The best Rieslings are matured in the coolest cellars in large barrels, containing about 1,200 Liters, made of oak from the Hunsrück northwest of the estate.
The aging of the red and white burgundies in small barrels has a tradition at the Diel estate that dates back to the early 1980s. The 228 liter barrels are made of French Oak. One small part of the barrels is replaced every year.
For the 2013 harvest, a new wine press building was put into operation at Schlossgut Diel. The grapes are transported into two pneumatically operated presses, which ensure a very gentle pressing. Subsequent fermentation takes place in oak barrels, or stainless steel tanks.
In the late 1980s, the artist Johannes Helle converted the stainless steel tanks of the Diel estate into pieces of art, turning them into a formidable sculptural landscape. Ever since the painter has returned to Burg Layen once a year to develop his technique on these unique paintings.