Simplify the following text for a Grade 9 native English-speaking person.
Original: El Puerto de Santa MarÃ a ( Spanish : `` The Port of Saint Mary '' , locally known as just El Puerto ) is a municipality located on the banks of the Guadalete River in the province of CÃ diz , Spain .
Simplified: El Puerto de Santa MarÃ a ( commonly called El Puerto ) is a city located on the banks of the Guadalete River in the province of CÃ diz , Spain .