Doctor Who is currently filming in Croatia, the BBC has confirmed. The location work is for Matt Smith's first series as the Doctor, which is being made and promoted by the BBC as Series One.
The programme is currently shooting in the small coastal town of Trogir in Croatia, for an episode due for transmission in the Spring of 2010.
A local blog has posted several pictures from the location shoot here. A very rough translation of the text can be found here.
Additional reports can be found here and here.