Pororoca

It could be also a Portuguese version of the term poroc-poroc, which in an indigenous' language was a way of expressing the act of destroying everything.

The tidal phenomenon is best observed on biannual equinoxes in September and March during a spring tide.

On an equinoctial spring tide, the Moon and Sun fall into direct alignment with the Earth, and their gravitational pull is combined, bringing the Pororoca and others around the world to their peak.

Since 1999, an annual championship has been held in São Domingos do Capim (on the adjacent Guamá River).

In 2003 the Brazilian Picuruta Salazar won the event with a record ride of 12.5 km (7.8 mi) lasting 37 minutes.