Cape Town - Hopes that Robben Island's voters would hear their results first were dashed when the last ferry left, with more votes expected before the 19:00 cut-off time.
An official at the Western Cape results centre said earlier that votes cast at the heritage site could be the first in, if everybody voted by the time the last ferry left at 16:30.
That would have enabled the ballot box to be put on the ferry and taken to the mainland for counting.
However, not all of the 143 registered voters had voted by the time the ferry left and, by law, the station had to stay open until 19:00 to accommodate everyone.
The option of sending scanned results to the nerve centre in Century City had also been ruled out because of a glitch in the communication line between the mainland and the island.
The ballot box was now expected to come over to the mainland on the first returning ferry on Thursday.
The island is known mainly for the high security jail where many anti-apartheid stalwarts were incarcerated, including three presidents - Nelson Mandela, Kgalema Motlanthe and Jacob Zuma.
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