The Rhine Falls are the largest water falls in Europe.
Take the bus no. 1 direction '''Neuhausen''' (10 min ride). The bus driver will mention the bus station named after the water falls, so you won't miss it.
Public Transportation: Take a train to '''Neuhausen am Rheinfall'''. A walk alongside the river takes 30 min and is well worth it. If you don't like walking for so long, take a train to '''Schloss Laufen'''. The train will drop you off just beside a castle that is right next to the falls. Note that the castle is closed in January and February.
By Car: Drive on the Highway A1 direction Winterthur, then switch over to A4/E41 direction Schaffhausen. Between March and December, get off the highway at '''Laufen''' and follow the traffic signs. In January and February, take the exit '''Neuhausen''', then follow the traffic signs. The parking space next to the Rhine Falls is very expensive (CHF 5.-/hr.), so if you don't mind 10 min. of walking, park in the inner city of Neuhausen. The parking is adjacent to the Lauferstrasse.
Entry is free on the right side of the river (Neuhausen). On the left side (Schloss Laufen), where it is possible to get very close to the water, the entry is ~CHF 5.