[Skeime]

Context, maybe just for others: Schiff is ship and Fahrt is ride, so eine Schifffahrt is a cruise (and without the article, it is also the term for seafaring in general). Anyway, you can see that Schiff ends with two Fs and Fahrt starts with one, so if you put them together to form a compound word, you get three Fs in a row, Schifffahrt. In pre-reform German spelling, this was deemed excessive, so one would write Schiffahrt, instead. The German spelling reform in the mid-90s changed this, so now you do the logical thing. (Whether the old way really was confusing and which way is more aesthetic are separate questions.)