Wernerseck
Take the A61 just to the west of Koblenz, and exit at the town of Plaidt.  From there go north on the L117 and then turn left on the Fraukirker Strasse.  This road will split, with a small chapel at the fork.  Go LEFT.  You will pass under the A61 and then reach a small parking area on the right.  Leave your car and walk a half hour and you will get to Wernerseck.  The castle, as can be seen, is quite isolated regardless of the fact that it is easily seen from the Autobahn.  It is a pleasant little hike and worth the trip, for Wernerseck is a unqiue ruin.
Wernerseck, or the Corner of Werner, was a castle held by a local lord determined to expand his domain beyond his immediate realm.  Werner claimed the Rhein, but found the Mosel much easier to raid in an effort to raise some hard cash.  He would plunder at will for some time, with no one in the area capable of besieging his castle.

So runs the legend preserved in novels. 

In reality, the castle was started in 1401 by Archbishop Werner von Falkenstein.  The main castle was finished in just about a year and served as a frontier outpost between Koln and Trier.  From the 16th through 19th centuries the castle was actually pawned to the Eltz family. 
Enter Wernerseck at your own risk!  The castle is in poor condition and subject to possible collapse.  Therefore, do NOT do what the kids are doing in the photo to the right!  Do NOT climb on the walls or attempt to enter sections of the castle that are blocked off.

But it is the poor condition of Wernerseck that makes it a unique castle to visit.  The stoney relic receives few visitors and one can wander the remains of the once mighty fortress and ponder life in such a place.  It is therefore anything but a tourist trap!
The main keep is 22 meters (about 71 feet) high, and shows obvious restoration work.  Just to the right of the left-most turret can be seen a box-like structure.  This is the top of the stairway.
The signs actually say that the castle is closed.  However, the grounds have been left open for those who wish to venture in.  Nevertheless, the sign also tells you very clearly to enter at your own risk.
The way to the castle, the view looking east.
The main trail is in good condition but the surrounding area is heavily overgrown.
There is evidence that some paste has been added many years ago to keep the walls from crumbling.  Yet, the authentic pieces used to build the walls are very obvious.  In this case, many of the pieces were flat stones about one inch thick that were stacked horizontally.  They were then cemented in place.  It is possible that some type of cement was spread over the stones so as to create a smooth effect.
After you enter the inner ward you will see the remains of a stairway along one of the walls.  Along the top of the walls is the remnant of the battlement, the stone footings still visible.
Another view of the same stairway.  The overall poor condition of the walls can be clearly seen.
Looking up one of the towers, the footings for the steps are barely visible.  This tower was mainly a watch tower and for minimal defense.