Surviving WW II almost undamaged, Heidelberg is how many other cities might have looked like before WW II. It is a typical fairy-tale like city, a city that is so atmospheric that it automatically creates that nice holiday-feeling. Touristic, small, cosy, and comparable to an Italian city like Pisa, or a Dutch city like Leiden. The city is holder of the oldest German University with a high standing reputation. It is situated along the Necker River in an very beautiful part of Germany.
further reading::
Oliver Flink / Norbert Kustos, Heidelberg, Published by Ellert & Richter Verlag, ISBN 9783831903207. A fine picture book to memorize sweet holiday feelings, or to warm up for it...
http://www.heidelberg.de/hd,Lde/HD.html. Website from the municipality of Heidelberg, with many interesting links for the visitor.