>>1818604istanbulfag here, until 2013 if you wanted to cross the bosphorus(which is a common thing everyone needed to do) under half an hour you had to take the ferry because the bridges would have insufferable traffic.
now we have a single train going under the strait and despite that i find myself using the ferry way more often because the docks are always closer to where everyone wants to go and ferries still take less time if you miss your train and have to wait 10 more minutes for the next one.