If you'd love to add a bit of extra culture to your escape, put Museu de Santarém on your must-visit list. See if guided tours are available or just look around at your own speed.
To visit this museum, make tracks to Prainha. You'll find loads of other interesting attractions in the area, such as Maracana Beach, Paraiso Shopping Center and ZooFIT - Zoologico de Santarem.