Huge cemetery. If, like many, you are only going for the famous composers then depart the tram at tor 2 and enter, you're only a 5-10 minute walk. Strauss, Schubert, Beethoven, Brahms all in the exact same plot. There is a memorial to Mozart but this is not where he is buried. Also on the same plot is the grave stone featured on the front cover and video for Vienna by Ultravox. 10 minutes walk from here you will find the grave of Austrian pop star Falco and it's clear how adored he was/is. Fascinating experience. You could aownd hours walking around I am sure, we went just for those I've mentioned. Probably about 40 minutes on the tram from the centre but we'll worth it.