Kobern-Gondorf is abt 15-20 mins drive from Koblenz and the drive there is lovely. It is a small sleepy old town by the river, just as i imagined how a town by the Rhine should be! (unlike Koblenz....heheheh). and around it are vineyards (on slopes).
When we reached there, our first thought was that we should have stayed here instead of Koblenz :p So we spent some time walking around and admiring this quaint old town. as part of the town was on sloping hills, we drove part of the way to explore it.
They have 2 castles here, Schloss Liebig and Schloss von der Leyen. The latter, we drove right through it on the way back -- quite an interesting building.
On the way to and from Burg Eltz, we passed by MunsterMaifeld. We made a stop on the way back from burg Eltz. Smaller and less interesting than Kobern-Gondorf but with some really old houses.
Overall, enjoyed Kobern-Gondorf better and definitely nice side trips from Koblenz :)