Uber's most expensive service? An intercontinental UberBoat.

The car service adds boat rides in the Middle East to its list of transportation options.

Want a ride to Istanbul? There's an Uber for that.

Uber’s latest transportation service may be the most expensive ride-sharing option the company offers. UberBoat, now available in Istanbul, will buzz passengers across the Bosphorus Strait in speedboats.

Uber has teamed with Turkish boat company Navette to offer rides for anywhere from $18 to $161, depending on ride length, with cost-splitting options possible among the 6 to 8 passengers. While protesters complain that UberPop and UberX offer prices that undercut taxi fares, cost does not appear to be the primary draw for Istanbul's UberBoat.

Cheaper ferries and two free bridges currently connect the European and Asian sides of Istanbul, but traffic over the bridges is almost continuously heavy. Construction has begun on a third bridge as well as a tunnel under the Bosphorus, but the projects have been stalled.  

UberBoat's main draw could be simple efficiency. Traffic jams in Istanbul rank second worst in the world, based on number of starts and stops per mile. Ferries cross the Bosphorus for only a few dollars each way, but their long lines and frequent stops have given them the nickname of "Beggar Ferry."

Like the Uber car service, which has operated in Istanbul since last summer, UberBoat is available via smartphone app and charges passengers' credit cards at the end of the ride.

Uber has dabbled with water taxis in other cities, though this is their first permanent offering, as well as the first inter-continental service for the company. Uber launched boat experiments in Boston, Sydney, Amsterdam, and Baltimore, but boats ran in Sydney for only a few hours, while Bostonians could Uber across Boston Harbor for two weeks during June 2014.  

Uber may be trying to redeem its name by providing a service that offers an alternative without undercutting the competition. Paris and other cities have been working to regulate the ride-sharing service, while numerous cities, states, and countries have banned Uber outright.

Istanbul already has plenty of taxis, with over 17,500 licensed drivers in the city, but UberBoat may have found a new niche market for commuters and tourists interested in crossing the intercontinental city without congestion and in the fresh air.