Avenue Fonsny

{{Short description|Street in Saint-Gilles, Belgium}}

{{Use British English|date=January 2022}}

{{Use dmy dates|date=January 2022}}

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| name = {{unbulleted list|{{native name|fr|Avenue Fonsny|italic=no}}|{{native name|nl|Fonsnylaan|italic=no}}}}

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| image = Avenue Fonsny in June 2016.jpg

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| caption = The {{lang|fr|Avenue Fonsny|italic=no}}/{{lang|nl|Fonsnylaan|italic=no}} in Saint-Gilles, next to Brussels-South railway station

| map_type = Belgium Brussels#Belgium

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| map_caption = Location within Brussels

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| location = Saint-Gilles, Brussels-Capital Region, Belgium

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The {{lang|fr|Avenue Fonsny|italic=no}} (French) or {{lang|nl|Fonsnylaan|italic=no}} (Dutch) is a major street in the Saint-Gilles municipality of Brussels, Belgium. It connects the {{lang|fr|Place de la Constitution|italic=no}}/{{lang|nl|Grondwetplein|italic=no}} on the south-west of the Small Ring (Brussels' inner ring road) to the municipality of Forest, where it is continued by the Avenue Van Volxem/Van Volxemlaan. It bears the name of a former mayor of Saint-Gilles, Jean-Toussaint Fonsny.{{Cite web |title=Avenue Fonsny – Inventaire du patrimoine architectural |url=https://monument.heritage.brussels/fr/streets/10601057 |access-date=2023-11-04 |website=monument.heritage.brussels |language=fr}}

One entry to Brussels-South railway station is on the Avenue Fonsny. The street also runs parallel to railway line 96.