Praça da Alfândega e Entorno, Historic square in Porto Alegre, Brazil.

Praça da Alfândega e Entorno is a central square in Porto Alegre surrounded by historic buildings including the Ado Malagoli Museum and Santander Cultural center. The space functions as an important public gathering area with architectural character in the city center.

The square's origins date to the late 18th century, when the area was Porto Alegre's river port. On 2 July 1783 the council ordered a stone quay on Lake Guaíba; in 1804 governor Paulo Gama added a pier with 24 stone pillars. In 1912 the old Customs building was demolished and a 100-metre embankment into the lake fixed the square's current shape.

The Porto Alegre Book Fair has been held here annually since 1955, according to the Portuguese-language article (the English version gives 1855). It fills the square with bookstalls and music, theatre and dance performances. The square was renamed Senador Florêncio in 1883, and the name Alfândega recalls the customs house that once stood in its middle.

The square opens toward the Guaíba along the axis of Avenida Sepúlveda, where a paved path planted with California palms once led to the gate of the Mauá wharf. The Monument to General Osório, by sculptor Hildegardo Leão Veloso, stands at the centre with an equestrian statue, water mirrors, benches and fountains, a natural orientation point.

The square's centrepiece is the 1923 equestrian Monument to General Osório, by sculptor Hildegardo Leão Veloso, set among water mirrors, benches and fountains. Nearby stood the Chafariz da Imperatriz, a French cast-iron fountain inaugurated by Emperor Pedro II in October 1865, topped by three chubby boys back to back; it later vanished without trace.