The Thomson Spirit sailed down the river to dock at around 8am but spent close to an hour and a half without being able to move.
It eventually managed to dock at 9.20am, but only performed its turn-around manoeuvre to sail out of the city at the end of the day, at high tide.
Problems concerning silting in the Arade River are, newspaper Correio da Manhã reports, well-known to the Algarve and Sines Port Administration, and, the report claims, proper dredging of the riverbed has not been carried out for almost a decade.