While staying in Munich, I had always planned on seeing Dachau and I found getting there very easy (a relatively short trip on the S-Bahn from Marienplatz). I was travelling in a group, including one lady with a knee injury so there would always be mobility issues. We started walking from Dachau station to the KZ (really well sign-posted) but after finally asking a local we were told that it would be several more kilometres to the site. (ADVICE: look out for a bus from the train station to the camp).

We decided that as we wanted to go at our own pace, an audio guide would be best so we rented one each very cheaply in English. These were really useful and provided us with additional info to the signs and notices posted all over the camp. The camp museum in the maintenance building was INCREDIBLY well laid out, informative and didn't really hold any punches. It had everything from documentation (passports etc) of prisoners to video footage of interviews with survivors. The camp itself is very accessible to people with disabilities and seems to be as well-preserved as one could hope.

However, I and several others from our group did take issue with one thing... the other visitors to the camp.
We couldn't really believe our eyes when we saw what some of them were doing and that they were being so disrespectul of their surroundings and the horrific events that had taken place on the site.
Here are some examples:
1) Tourists posing for family photos (cheesy smiles and arms around each other) IN FRONT OF THE INCINERATORS IN THE CREMATORIUM. In front of the actual incinerators where bodies were disposed of this was happening... which seemed highly inappropriate and upsetting to lots of us.
2) We saw many tourists of all nationalities posing with the infamous gate (the black metal gate stating "Arbeit Macht Frei"). They were posing behind the gate, clutching it and smiling, with their photographer on the other side taking snaphots, i.e. they were pretending to be prisoners.

These are only some examples of what these idiots got up to. You may think that I'm taking it too seriously, but if you consider the atrocities of Dachau and have any sort of a heart then it is difficult not to anger at this moronic conduct.

So, in conclusion;
1) Leave at least 2-3 hours for the visit (opens 9-5, I think)
2) Get a bus from the train station
3) Rent the audio guide
4) Try to really feel the environment and think deeply about the information presented to you. In establishing a human perspective on the history of the site, this is really quite important.

Also, bring water with you as you won't be able to buy it at the camp. Use the WC before you begin walking around - there is only one set of toilets and they're at the entrance.

A must-do excursion during your visit to Munich and/or the Bavarian Alps. It is very humbling to actually be standing in the middle of a real concentration camp. The memorials on the site are haunting, the museum very well done, and the Creamatorium will literally take your breath away. Every human being needs to make a visit there.

Plan for at least 4 hours as you will want to take enough time to walk around the whole site. Definitely rent the audio guide (3 euros), although one can definitely be shared by two people (they are large and pretty loud). One point of advice, the audio guide has dozens and dozens of recordings you can listen to. We caught on after awhile that there is a "basic" intro audio and then usual 2-4 other audios for each area that go more deeply into key topics and sometimes include interviews with survivors and liberators. This audio guide really helped "make" the visit for us in terms of helping us to understand and appreciate what we were seeing. Don't rely on the printed guide or placards, get the audio.

We would also recommend the film that is shown in English a few times per day. Very touching and brings you to the true reality that was Dachau.

Also, be aware that no food is served on site (although we saw that they are building a cafe at the entrance, don't know when it's slated for opening), and the only thing close-by is a McDonald's.

If you're in the Munich area, Dachau is a nearby destination (easy to get to via public transportation) that is worth visiting. You'll see the remains of this "model" concentration camp upon which all the other ones were built. From the "arbeit macht frei" ("work will set you free") on the gate, to the barracks, to the torture room, to the crematorium, this memorial will give you a sense of what went on within concentration camps.

We took a guided tour of the camp, but we found out everything was described in English, and at most, an audio guide is all that you'll need. The experience is disturbing, depressing, moving and necessary.

I have visted Dachua several times, taking my daughter the most recent visit. This is surprisingly localized camp. Dachau is a quick jaunt from Munich or even from Garmish (Which was our most recent starting point)
This is a well organized museum. The information is well presented and in a manner that presents the progression of Nazi Germany. The grounds are labeled and the guide-books are easily accessible. The bookstores are useful but not giving the appearance of turning the site into a market.
There are also many places to sit and reflect on the occurrences of this historic place.

Be certain to vist the floral arrangements that were place by the Israel Olympic team only hours before the Munich Olympics in 1972...