The nearest airport is Lisbon. Praia d'el Rey is an hour or so north by car.

Easyjet, British Airways, TAP and Monarch all operate from various UK airports. Aer Lingus operate a service to Lisbon from Dublin.

Once you have arrived in Lisbon the best option would be to hire a car for the duration of your stay. This will allow you to explore the many different aspects of this beautiful part of Portugal.