It's easy to reach Estremadura and the Ribatejo from Lisbon because both provinces begin as extensions of the city's northern suburbs. There are two principal access roads from the capital: the A1 (also called E80 and IP1), which is the Lisbon–Porto toll road, provides the best inland access. The A8 (also called IC1) is the fastest route to the coast. From Porto there's easy access via the A1.
The roads are generally good, and traffic is light except for weekend congestion along the coast. Parking can be a problem in some of the towns, but larger hotels don't usually charge for parking.