Demonstrators on Saturday waved posters demanding a general strike after measures drawn up to address mass anger over the eviction of María del Carmen Abascal, and other housing issues, were rejected in parliament, according to reports.
The protest, which organisers said drew tens of thousands of people, came in reaction to the dramatic eviction on Wednesday of the 87-year-old woman from the Madrid apartment she had lived in for decades.
"We're here because housing is a problem that already affects all of society, all ages and classes," said protester Dora Garcia, a 55-year-old nurse. "And we can't keep maintaining this. Housing is a right and we don't have it."
Ms Abascal, taken out of her home on a stretcher in the upscale Retiro neighborhood, was greeted by protesters and supporters as she was loaded into an ambulance. Spanish media reported that her father first rented the property in 1956 and she continued as the tenant after her parents died, during which time there was a rent cap.
The building changed ownership in 2018, and Urbagestión, an investment fund that later bought the unit, raised her monthly rent from 500 euros to 2,650 euros, later lowering it to 1,650 euros, which she still could not afford on her pension, according to the Madrid Tenants' Union, which organised Saturday's protest.
"This whole housing situation is heartbreaking," said protester Simón de la Riva, a 43-year-old teacher. "Maricarmen has been, in a way, the last straw that sparked this social unrest, but we've been dealing with this whole issue for a long time now. It's unacceptable that vulture funds are buying up homes, that people can't afford to live, that entire families are being evicted, and that an elderly woman has been evicted."
At the end of the march, protesters sat down in the Puerta del Sol plaza, with some pitching tents planning to stay at least the night or until police forcibly removed them.