Singapore city sightseeing tour operator City Tours run both the FunVee double decker open top bus and the Captain Explorer DUKW. The FunVee open top bus allows you unlimited hop-on-hop-off sightseeing, its three routes (City attractions, Ethnic attractions and Sentosa attractions) taking in over 30 attractions and passing by over 48 hotels. The Captain Explorer DUKW (pronounced 'duck') tour runs hourly one-hour tours on board an authentic revamped Vietnam War era vehicle, taking in the landmarks of the Colonial District on wheels before splashing into the Singapore River to see them from the water. Tickets for both tours can be bought in conjunction with Singapore Flyer tickets and other attractions.