Passau's city is spread out a little, but most places you will want to see are within walking distance. Busses are also common. You can walk 20 minutes from the city center and be in Austria.
Passau was founded by the Romans back when they were a big thing. Much of the money in the city was made from the salt business, with the salt coming from Salzburg in Austria. In the middle ages, Passau's Saint Stephens church was the head of the local church district which extended all the way to Hungary. Most of the old buildings survive today and are in active use.
Nowadays Passau is known for its historic buildings, its University, and its location at the 3 rivers and the last German train station before Austria. Like much of Bavaria, it's also predominantly catholic. If you look very closely, however, you can spot one protestant church.
It snows in winter, and it is warm to hot in summer. Quite often you get over 30 degree celsius days. Riverfloods from the Danube and Inn are not uncommon in Passau.
It is NOT your typical backpacker destination, although backpackers have been known to turn up occasionally. There is only one backpacker-type Hostel that I know of, but it's also student housing, and is in a castle overlooking Passau's city-center. It's a bit of a climb, but it is apparently quite nice. There are plenty of Pensions (hotels/motels) in and around the city.
Most of tourists Passau receives are on river cruises going along the Danube. Most tourists here are native German speakers, so don't think you can go everywhere and speak English, although you may be surprised how common it is.
There is a well known bike trail leaving from Passau and going right to Vienna, by the Danube. If you're up for a bit of a hike, this trip apparently takes two weeks, but everyone I know who has done it has made it in 8 to 10 days. I've also heard of someone who took a small motorboat down the Danube to Vienna. They kept approximately the same pace as the cyclists.
Beer, Beergardens, Lederhosen, etc.
Passau has 5 breweries. Every pub or restaurant seems to be associated with one of them. The beer is delicious and cheap.
Like the rest of Germany, buying alcohol out is more expensive than buying it at the supermarket. Service has a big pricetag here. The student pubs are almost as cheap as a supermarket, though.
There are a few beergardens in Passau, and a couple that pass the "real beergarden test". That being, you can bring your own food to them regardless of whether they sell food themselves or not. Beergardens developed because breweries used to plant trees atop their underground cellars to keep them cool, and the result was a really nice atmosphere to relax with a beer in hand. Beergardens tend to open in the spring and close in the fall as the weather cools again.
Lederhosen .. you all know what they look like. They're probably the first thing you associate with Germany after beer and bloodshed. People don't walk around in lederhosen on a day to day basis, but for special events many locals do choose to wear them!
Passau University is famous in Germany for its Law Degree which has a special focus on English law. Lawyers graduating from Passau are in good stead. It also has an excellent international business course, economics course, informatics course, language courses, and others I've surely forgotten or haven't heard of yet. There's a German-for-foreigners course at the university, as well as external pay-for courses.
German students receive free tertiary studies, and I'm lead to believe that foreign students can study here cheaply also. The catch is that German is a must unless you're taking only German-for-foreigners subjects.
Places to see
The Bavarian Forest is not too far away by car. It has a national park where you can see many types of animals. Unfortunately they keep the wolves caged. The poor animals probably haven't tasted human blood in years!
A nearby district of Passau still has a "Pranger" standing. A bad-person would be locked in at the neck, hands, and feet on a raised pedestal in the town square and left as punishment. People could throw things at them. This punishment was handed out by the church, for your own good.
There are a bunch of old buildings, churches, cathedrals etc. to see. Most of the roads in the city center are cobblestone.
Things to do
When university is active, the inner city is owned by the students. Many know each other, but it's easy to get talking to them. Most people will be thrilled to meet overseas visitors. Although they will be curious about why you came to Passau. You can tell them that "Robert from Sydney Australia" wrote about it on WikiTravel.org. They might just know me.
It is, however, a small town. When exams are on, less people will be in the city partying. Often there is only a couple of places you can seriously consider going out to on any day of the week. Thursdays, Fridays and Saturdays are the nightlife nights. On Thursdays, you have bar-trivia at the Irish Pub where your group can win EUR60 (or up to EUR120 with the jackpot). Questions are in both English and German. On Thursdays, the LOOP has free champagne for girls (and guys not ashamed to drink champagne their female friends get for them). There are also a couple of Student Pubs in the area, which offer very cheap drinks, pool tables, darts etc. There are a couple of nightclubs in Passau, one in the city which is busy from late on Wednesdays and weekends.
You can take a cheap short cruise on the rivers, although I don't know if you can find one where the commentary is in English also. Most likely you can. It's a relaxing cruise, regardless.
In May - usually at the beginning, although this year it was postponed until the end - there is the Maypole festival (called Maibaum Kraxeln) held in nearby Austria (it's not legal in Germany for safety/insurance reasons). There are busses leaving from Passau. This yearly event has local men tarring their feet and hands and climbing a very tall pole without harnesses. There's a race to the top (people race seperately). The Guinness World Record is held by a local guy. After the competition they usually make great photo opportunities by all climbing the pole and passing the guy at the top a beer. I believe anyone can take part, but check that your personal insurance covers it! You can also have a somewhat safer sack-fight on a raised wooden pole, which is also quite fun.
Passau also has a twice-yearly fare, with rides and beer halls with bands. It was great fun. Lederhosen were rampant, people got up on the table and swayed back and forth singing classic songs. (The author starts singing, Ge-müt-lich-keit!)
I've also spotted walking night-tours in the city.
If you're here on a warm day, you can take yourself upstream a bit on the Ilz and go for a swim where locals and students sometimes go. One place is just near a sign that says "No Swimming", the other is further up by a dam.
The tourist office down by the Donau in the city can assist with specifics.
Passau is a great town. It isn't a super-commercialised tourist destination. You probably won't find a big mention in your lonely planet guide book, and that's GREAT!
If you want to come to Germany to study, don't give your destination another thought. Even if you want to learn German, it's great. It's cheaper than a big city, accomodation is readily available, and it's strategically located close to Austria (cheaper fuel if you drive!), the Czech Republic, Switzerland, and of course the rest of Bavaria!
If you're on a whirlwind tour around Europe, Passau probably isn't the place to go (unless you happen to catch a local event). However, if you have some time to spend in Europe, and would like to relax in a beautiful small city, come! Drop by the Irish pub and chat to the owners, a Welshman and a Scottish/Irishman. You might even find me there.
G'day. My name's Robert and I'm from Sydney, Australia. I live in Passau just now with my German girlfriend. I'm one of two Australian Robert's in Passau currently. And one of five I am familiar with in total. Three of them are on student exchange with Passau University. One of them is just visiting his German girlfriend who he, like me, met when she was in Australia on exchange last year. I'm expecting some fresh foreign blood soon with the new semester, and hopefully a few more English tourists.
Edited by Jose Capco :)