Well, not a real elephant, but the caterpillar of the elephant hawk-moth Deilephila elpenor (in German: Mittlere Weinschwärmer).
I could see it wriggling across the lawn from our terrace, it is so large! I put a 1 Euro coin in its path so you can get an idea of its size. A Euro has a diameter of 2.325 cm, so just under an inch in old money.
I hope I get to see an adult moth one day (or night more likely); looking on t'internet they are quite astounding.
More information about the elephant hawk-moth on wikipedia.
I wonder how it got its German name though? Weinschwärmer means something like 'wine enthusiast'!