The protesters say the tower will destroy the historic city
About 3,000 people have rallied in St Petersburg against plans to build a huge skyscraper in Russia's former imperial capital.
Demonstrators voiced anger at the city council's decision to approve construction of the 400m (1,312 ft) Okhta Centre for the gas giant Gazprom.
They said the tower would spoil the city's historic skyline.
The UN cultural body, Unesco, has said building the tower could endanger the city's status as a world heritage site.
The Okhta Centre's designers describe it as a "twisting glass needle"
On Saturday, demonstrators chanted "No to the tower!" and "History is more important than money!" at the rally in central St Petersburg.
"This action will destroy my city, the city where I grew up, and the city that I want to save for my grandchildren," Galina Safronova, aged 55, was quoted as saying by the Associated Press news agency.
Russia's culture ministry is also objecting to the building of the needle-like glass tower.
The ministry has asked prosecutors to examine whether last month's official approval of the project violates Russia's federal law.
The skyscraper has been designed by British firm RMJM and would cost some $2.4bn (£1.5bn) to build.