You can get to and around Bratislava by boat easily. There is a direct connection between Bratislava and Vienna by the Danube river. There are two main companies which operate on these routes:
TWIN CITY LINER
Routes: Bratislava – Vienna, Vienna – Bratislava
Times: from 10:30 in the morning, the last cruise from Bratislava at 18:30, on Fridays and Saturdays there is an extra trip from Bratislava at 22:30, arriving to Vienna at midnight
Season: from 11th April to 2nd November + the Christmas trips (check info below)
Prices: 20 – 35 € one way, depending on the season and weekday/weekend
CHRISTMAS TRIP from Vienna to Bratislava (not the way around unfortunately) every Saturday and Sunday, from November 22nd – December 21st 2014. My recommendation is to take a train to Vienna (one way ticket costs around 7 €) and from there take a one way trip on a ship back to Bratislava (35 €).
Departure from Vienna is at 1am, departure from Bratislava at 5pm.
Price: 35 € per person / one way.
Routes: Trips between Bratislava and Vienna, sightseeing trips of Bratislava, trips to Devín Castle and Čunovo.
Operates: on specific days depending on the season
Times: at 9:00 in the morning from Bratislava to Vienna, departure from Vienna at 17:30/16:00 depending on the season
Season: Bratislava-Vienna from 23rd April – 26th October, cruises by sightseeing boats April – September
Prices: Bratislava-Vienna 18 € one way, 29 € return; sightseeing cruises 2-10 €
More info on:
The shipping port for both companies is situated on the north coast of Danube, at Fajnorovo Nabrezie 2 (right by the building of the Natural History Museum).
You can book your cruise in advance.