Fairly long ride today from just outside of Flensburg, about 100 km - though in the absence of perfect navigation, missed turns and resulting backtracks brought this total to somewhere around 120 km. The day started out with a quick hop down to Schleswig, where we grabbed a generous lunch of pizza, watermelon, pretzels, and beer; as we noted before, sustaining this level of activity for several hours each day requires an enormous amount of food!
After this, we had a slight detour towards Kiel - the highway signs are not always obvious, especially at multi-highway junctions. It took a bit of help from an attendant at the nearest petrol station and a closer look at the map to get back on track, but we managed to catch the error before we got too far out of Schleswig. We did have another spot of misdirection in getting onto the correct bike path for Neumünster, and were forced to push our bikes up a set of stairs alongside the highway out of Schleswig. With those two obstacles overcome, we were now on our way to Neumünster.
We hit Rendsburg next, where we ended up missing the highway again; fortunately, we corrected this much faster than our previous misadventures out of Schleswig. (I suppose we're learning from experience, albeit slowly!) Upon asking the locals for directions, we received some cryptic advice: "This road leads down to the bridge, where you will find a ferry hanging from a bridge." This seemed like utter nonsense at the time, but turned out to be accurate - for there, under the railway bridge, was a section of road suspended by four thick cables for the sole purpose of carrying pedestrians and motorists to the other side. (Why did they not simply build another bridge? This is an excellent question - perhaps they wanted some Rube Goldbergian practice.)
The bike path from Rendsburg to Neumünster was another adventure altogether; this leads through farmland and backcountry gravel roads, which are understandably unfriendly to touring bikes. We encountered loose sand at several points along this path, causing us to careen into tailspins that nearly toppled us (and our weighty gear) off our bikes. That said, the path was quite beautiful in some parts, especially where it passed by majestic groupings of wind turbines or tree-lined alleyways.
Our final challenge of the day was finding the campsite around Neumünster; it was not actually in the city proper, but rather some 5 km or so out in the surrounding countryside. Nevertheless, we mustered enough persistence and last-minute energy to arrive there and set up camp, whereupon we promptly passed out.
So far, the greatest difficulty in navigation has been finding our way out of cities; the routes in between are fairly well marked, with frequent signs listing distances to nearby towns. The best remedy is usually asking for help; unless you have a decent GPS navigation unit or printed copies of every last map tile on Google Maps, chances are the locals know the area better than you could ever hope to. It might be difficult to ask, particularly if your command of the language is somewhat lacking, but you will likely ascertain enough of the intended meaning from frantic hand signals to figure it out. (At the very least, you can get going in the right direction and ask again.)