The campaign for residents of the Algarve is valid for visits between the 13th and 30th of September. The normal 1-day ticket for Algarve residents, per person, is 22€ (11-64 years old) and 12€ for junior (>= 10 years) or senior tickets (>= 65 years).
To benefit from these conditions, the ticket must be purchased, exclusively, at the park's online ticket office, and the presentation of a proof of address is required on the day of the visit (e.g. water, electricity, gas, communications, student card, rental contract, as long as you have a printed address + valid ID). The special price is applied per person to the resident and to one more guest, resident or not.