The airport in Halifax is not near anything, including Halifax. We bought a boat that was in the Chester area and found that it was pretty convenient to take a bus from just outside the marina gate to the Halifax bus station and then another bus to the airport. If you find a suitable marina contact them and ask how one gets to the airport from their location.
In South Africa doing lots of boat stuff. Departure north from Cape Town around December 15th. Arrival in the Caribbean around the beginning of February, after 5300 miles or so.