Grafenstein
Grafenstein was constructed to replace a stone fortress already extant on the site.  Construction was during the last half of the 1100s, being done by the Counts of Saarbrucken.  It was later passed to the Counts of Leiningen who were related to the Saarbrucken family.  The castle was in a strategic location as it bordered the intersection of three rival districts, the diocese of Speyer, Worms, and Mainz. 

The keep was constructed first, followed by the surrounding palas and outer walls.  By the early 1200s, the castle was placed under the authority of a local governor who maintained and enlarged it according to the plans provided by the family.  It was from this governor that the castle received an early version of its present name.  By 1345, the castle had been mortgaged a number of times to cover debts that local revenues could not cover.  By the end of the century, the castle was almost completely mortgaged to Ruprecht I of the Palatinate.  The Palatinate passed its ownership to other families and eventually it was returned to the Leiningen family, who held the castle to 1535.  During the Peasants War of 1525, the castle was besieged by an Alsatian peasant army, captured, and sacked.  A burned out wreck was useless, and the Leiningen family sold the castle back to the Palatinate for 9,000 guldens.  The latter rebuilt the structure at the cost of over 5,000 guldens and made it his principal residence.  With the Count of Palatinate's death, the castle first was held in trust for the count's minor children, but later passed to the Counts of Baden-Baden.

During the Thirty Years War, the castle was garrisoned by Imperial Catholic troops, who supposedly burned out the structure through rank carelessness!  The remains passed to the local government of Baden-Durlach and some restoration work was done in the 1930s and 1980s. 

Locals have dubbed the castle the "Merzalber Schloss," named so for the local town.  These photos were taken in 2008.
Grafenstein has a unique seven-sided tower, and to my knowledge it is the only castle with such a keep.  The keep has been restored internally and this allows a fantastic view over the entire region.  It is one of the best ruins I have seen and is thus on my list of the best castles to see!

Above, the main gatehouse leading towards another gate to enter the outer ward.
Right, the second gate along the outer wall.  Beyond this gate one turns right to enter the outer ward.  The vegetation adds real allure to this castle, making it a real treat to visit.
Left, the walls of the palas, a multi-level residential area.  The partial "tower" that has the small windows in the right-center is actually a sanitation tower, with the toilet areas apparently on several levels.
Left, as you enter the above gate you can see the beam placement intent for securing the gate.  While some mortar restoration has been done, the rest is authentic.
Left, the main gate that leads to the outer ward.

Below, another outer work beyond the main gate.  A "mouse hole" entrance would allow movement of indivdual personnel.  The main gate's ruined tower can be seen beyond.
Right, a walk along the outer wall demonstrates how difficult this castle would be to take.
Left, a view from outside looking up to the walls of the palas.















Left, a close up of the restored arched section of the main gate leading into the outer ward.  The stone sections above the concrete arched items is authentic and was apparently taken from the ground and reset during one of the restorations.