This is truly worth the visit, and still costs a very reasonable amount. EUR9 at the time of writing for the palace and its gardens.

You can reach there using the metro, the stop is the last one on that line, Versailles Rive Gauche (now, maps conveniently state "Chateau de Versailles"). Do not get off on the earlier halt, also called Rive Gauche.

The Chateau is only a very short walk. Just turn right from the main entrance from the station and then turn left. You will see the walk up to the palace. There are souvenir shops on both sides of the street.

The palace grounds and gardens are awe-inspiring. You can spend a week here, but I had about 6 hours. Be sure to rest occasionally, or better use the mini-trains if you are not used to walking. The length of the tour is supposed to be 5km. The gardens seem to stretch as far as the eye can see, with lakes and ponds with little boats on them. There are innumerable bronze fountains in the gardens if you walk in any direction, several large sculptured fountains in the walk directly facing the rear of the palace proper. This is one of the most awesome palaces I have ever been to, only Sanssouci in Potsdam, Germany may be slightly bigger in area if you take the new palace and the whole park into account.

The state rooms themselves are gilded and very ornate with quite a lot of Louis XIV furniture, but perhaps not as ornately as say, Windsor Castle's restored wing and Schönbrunn in Vienna. The rooms are also always very crowded and you can keep bumping into people taking photographs if you are not careful.

There is a war gallery, which has art depicting great French battles from the 5th Century to the 19th. Be sure to spend some time in studying these giant canvasses. They are as interesting as those in the Louvre in central Paris and the Getty in L.A.