Cuba's main airport does not have enough structure...

Cuba's main airport does not have enough structure for the growth of demand and tourists from the island. It needs repairs and to increase its size both on arrival with immigration, and the checkin of the airlines.
The system used by Avianca is absurdly slow and you will need to be patient in the queue.
The airport is a little far from central Havana or old Havana. Approximately 40 min and the taxi must be a maximum of 30 Cucs (approximately 30 Euros). Consider sharing with people with the same destination and sharing the account.
Upon arrival at the airport, there is a currency conversion box with a quote very similar to the quote in the city center. My suggestion is to take Canadian dollars as there is a fee for those who exchange for euros and mainly American dollars.