It was built in 1933 as the first concentration camp and used mainly as a labor camp for political prisoners. Compared to an extermination camp like the notorious Auschwitz where over 1 million prisoners were killed, there were a still impressive yet much smaller 32,000 killed at Dachau.
What makes Dachau so important is that it was where the people who ran the entire concentration camp system were trained. Most of the cruel innovations for Hitler's mass killing originated at Dachau.
The Father and I first visited Dachau back in March at the end of our epic two week trip to Nuremberg, Berlin, Dresden, Prague and Munich. It was an awfully cold, freezing rain sort of day. I visited it again with my mother or our way back from Oberammergau last week. This time it was also cold and rainy. But perhaps the terrible weather is a fitting setting for the solemn, ugly place that the Dachau concentration camp is.
The first time we went we just used the audio guides provided at the camp which were mediocre, but the second time we went with a personal guide from Munich Walking Tours. (Only 2 private guide companies are allowed to guide inside the camp due to the sensitive nature of the tour.) It was a long tour (over 4 hours), but the guide was amazing and provided tons of helpful background info. Thankfully Penelope slept for over half of that!