In reply to Andy Fielding:
There are a couple of easy to medium difficulty ferratas near Zittau, almost at the end of the Czech/German border, near the border with Poland. If you are in the Elbe sandstone area it will be an hour's drive to get there. There are a bunch of places worth visiting in the area, so it may merit a day trip.
However, I would recommend to try some of the "Stiegen" (literally stairs or ladders) in the Elbe sandstone, which can be anything from long stairs to scrambles with short UIAA II section and one proper ferrata, the Häntzschelstiege ( https://klettersteig.de/klettersteig/haentzschelstiege/6 ).
My favourite, though, is the Rübezahlstiege, which climbs a chimney with the help pf some iron bars, and then ends in a cave that you have to climb through first horizontally and then upwards to reach the exit ledge.
Both are in the most scenic bit of the German part of the sandstone, roughly an hour south of Dresden and maybe a couple of km from the Czech border.
When I was living in Dresden my training round for the Alps was to connect all of the Stiegen around the Affenstein area, resulting in a 1500m height gain round trip.
Further down in the Elbe valley there is a sports ferrata in a quarry, but I have not tried it myself.
Closer to the other end of the Czech/German border in Bavaria there is a very nice ridge scramble to the top of Kleiner Osser. No idea about ferratas in the area, though.
CB
edit: if you are in the area you should go climbing, not waste your time on the ferratas! I know it has a scary reputation, but there are interesting and safe objectives at almost any grade, e.g. in Bielatal.
Just across the border from there is Tissa, which even has good top roping anchors and importantly proper bolts. (even though pavelk will pop up and tell you top roping is banned, the place is full of Czech climbers who do nothing else....).
The main bouldering area I know of is near Sneznik, just a couple of km from Tissa, but I have not done much there.
Post edited at 08:38