Santa Lucia train station is located on the bank of the Grand Canal, which is the easiest way to get to the city's main square on the water. Near the station is a Vaporetto stop called "Ferrovia", from which you need to go on route No. 1 or No. 2 and follow to the stop "S.Marco Vallaresso". A ticket for this type of water transport will cost you about 9.5 euros. Vaporettos to San Marco run quite often - the interval is about 10 minutes. You can find out the schedule and routes of the Vaporetto on the website actv.avmspa.it.