Which city's university did Marie Curie attend?

Marie Curie attended the University of Paris in Paris, France.

She moved from Poland to Paris in 1891, aged 24, to pursue higher education. At the university, known in her era as the Sorbonne, she studied physics, mathematics, and chemistry. She lived simply in the Latin Quarter and concentrated intensely on her studies, often tutoring in the evenings to support herself.

Curie earned a physics degree in 1893 and a mathematics degree the following year. Paris also became the setting for her scientific career. She met Pierre Curie there, conducted her pioneering radioactivity research in French laboratories, and later became the first woman to teach as a professor at the University of Paris after Pierre’s death.

The question asks for the city, so Paris is the canonical answer; the institution was the University of Paris. Warsaw was important to Curie’s childhood and early education, including her participation in the clandestine Flying University, but she did not attend a university there in the sense intended by this question. She retained a strong Polish identity throughout her life.