The Neckarsteig starts directly sporty: Around 1,200 roughly hewn natural stones lead you up the ladder of heaven, which brings you to the Königsstuhl. Up there you have a great view of Heidelberg. But you will not find your peace here often: the Königsstuhl is a popular tourist destination. Incidentally, if you find the climbing too strenuous, you can enjoy the ascent with a "funicular".
In itself, I would describe the Königsstuhl as a matter of taste, because it is fully developed - accessible by car and train. Accordingly, he is overcrowded too. You just go up to visit the fairy tale paradise or the several adjacent adventure trails, which are an absolute highlight for children (and really well done!).
However, if you just want to enjoy the view, you should be prepared for a number of people. Peace and quiet on the mountain is more likely to think on the more remote paths.
Since Heidelberg is a really wonderful city, especially with this beautifully preserved old town and the castle, I would definitely recommend a trip to any traveler.