To get up to the Philisophenweg, you can walk along the affluent residential area on the same side, higher and higher, but also quite a detour. The more direct route from the Old Town is to use the Schlangenweg, or "Snakes Road" up the hill from just across the Old Bridge. We did this after a heavy rainfall and it turned out to be quite an experience as wet cobbles are always...eh...interesting. Not for people with trouble walking as, apart from the cobbles, it is quite a steep gradient and here and there you have to negotiate stairs. We kept sending our daughter ahead as a scout as the road twisted and turned in a serpentine manner all along and the high stone walls revealed nothing of what lay ahead. Luckily, there were some viewpoints in the wall here and there, where you could sit down and enjoy the Castle.
Heidelberg is along a frequent IC Hamburg/Cologne to Stuttgart line so there are no problems getting here. Even if you are on the international Copenhagen-Cologne-Basel trains or something else, it is easy to get here by for instance changing in Mannheim which is only 20 minutes away by local S-train (see second website). The Hauptbahnhof (central station) in Heidelberg is not that near the Old Town so I recommend a taxi from it for less stress as the trams don't really take you to the "hotel end" of it.
Heidelberg is located about midway between Stuttgart Airport and Frankfurt Airport. You can take a train from the Hauptbahnhof to either Frankfurt or Stuttgart and get a connecting train from there. There are also direct buses (DM36) to Frankfurt Airport from the Renaissance Heidelberg Hotel
Heidelberg's public transport network is made up of buses and trams with Bismarck Platz acting as the main public-transport hub. Single-trip tickets cost DM3,20 and 24-hour travel passes are DM10. It is also possible to rent a bike for around DM25 per day
The Hauptbahnhof is located in the centre of town and is connected to the U-Bahn and S-Bahn public transport systems. There are direct trains to destinations throughout Germany.
From the Altstadt, just below the Heidelberg Castle, there are a few options to approach the castle--most are well marked. We have always chosen the relatively easy 10-minute walk up Kurzer Buckel from just behind Karlsplatz. This is a pedestrian-only walkway that is relatively steep at times, and has several sections of stairs. This approach takes you along the right side of the castle.
You are also able to drive to the castle entrance via Neue Schlosstrasse, but parking is very limited at the top. This route also takes you along the castle's right side.
I believe there is also a walking path up the hill from the left of the castle, but I do not know for sure how to get there.
Finally, there is a short cog railway called the Bergbahn that departs from Parking Garage 12 at the Kornmarkt. The first stop is the castle, then it makes several other stops as it climbs the mountain south of the town. The final stop is Konigstuhl, 550 meters above sea level, where visitors can enjoy a walk along the nature trails of the Odenwald forest. Cost is 3 Euro one way and 5 Euro round trip from the Kornmarkt to the castle. Round trip to the Konigstuhl is 8 Euro.
You can take the bus, the train, the metro with that ´ticket.
Ticket 24: for 1 person: 12 Euro, for 24 hours and you can drive so often as you like , and that not only in Heidelberg centre but also a little bit outside
maybe you just enter the bus 33 or 34 from the bismarkplatz and drive to ziegelhausen, about 8 KM outside and watch outside the window and enjoy the ride through the "Neckartal".....
Ticket 24 Plus: you can take up to 4 persons with you,same condition as the ticket above.
There are a lot of other good ticket, for example 3 days
If you know, you go from A to B and to C and the to D....that tickets will save your money.
Those visiting Heidelberg should know, that the Bergbahn to the hilltop i.e. the castle is undergoing renovations.
There is, in its place, a bus-service at the foot of the hill.
It costs 3.50 Euro for 'hin und zuruck' (2-way) per adult.
Heidelberg is compact enough that there's no need for any mode of transportation other than walking, assuming you stay somewhere close to the old town or the Hauptstrasse. You'll need to take a taxi from the train station to those areas, but once there you'll need only a comfortable pair of shoes.
Heidelberg is a baeutiful city, and not too big, so just walk it.. you'll see a lot more than you would any other way. A tour guide is nice too, because you can learn more ans ask questions.. ever though you will look like a tourist, but theer are lots of tourists, so you won't stand out. I don't reccomend walking to the castle though, unless your're one of those healthy people who like to sweat,lol....
I'm sure that a lot of people will be using the Ryanair service to Frankfurt Hahn to get to Heidelberg like we did,so I thought I'd mention that RYanair have buses running to different towns and cities in the area one of them being Heidelberg.It's a great service that waits for your particular flight before it leaves.It's a wee bit pricey though at 32 euros return
Unless you're feeling very flush,I'd advise you NOT to take a taxi in Heidelberg as I thought they were very expensive.They are all very comfortable and fast but even for short distances the price is high.Take the tram or walk.
In Heidelberg live many students and I guess this is one reason why many people get around by bike.
If you park our bike at the main station I suggest to remember quite good where you have put it ...
When you go to Heidelberg, try to be early in the morning! Try to get a parking on the right site of the river Neckar. If you're lucky, you don't have to pay for it. Otherwise you have to park your car in an official parking.
If you travel by train, you can take the tram or the bus to come to the Old Town (direction Bismarckplatz or direction Univeritaetsplatz)
Heidelberg is best explored on foot in the center, but a bike can be useful to get to out of the way places. To do some exploring in the less touristed parts of Heidelberg (Neuheim and Handschuheim), take the tram or bus north from Bismarckplatz.
Its also fun to take the bergbahn up the hill to the castle and beyond - great views!
Heidelberg is dead easy to get to. Only 1 hour train from Frankfurt (there's also a Lufthansa shuttle bus from the airport), 2 hours from Stuttgart, and 3 hours from Munich.
Coming by car is simple but subject to delays - the A8 from Munich, for example, is always backed up.
The rail station is a good 15 mins walk away from the old town, and not really that interesting a walk either. Train connections seem pretty good, Frankfurt around 1 hour, Mannheim 15 mins.
An alternative is to take tram #41 from outside the station to the Altstadt.