Image courtesy of Google Maps.

Worcester’s tallest building, the 24-story Worcester Plaza, sold Oct. 10 for $16.5 million, according to filings in the Worcester Registry of Deeds.

The Worcester Telegram & Gazette was first to report the story.

The buyer, Synergy Investments, owns several million square feet of office space in the Greater Boston market, including five buildings in downtown Boston and one in North Quincy. The best-known of these is Center Plaza, a sweeping, curved brick office building facing the Government Center plaza whose tenants include tech firms like Spotify and Grubhub. Synergy bought 10 Post Office Square earlier this year for for $238.72 million.

Synergy President David Greaney announced the purchase on Twitter Friday, describing it as the firm’s first Opportunity Zone investment.

According to Worcester land records, the 280,167-square-foot tower at 446 Main St. is assessed at $25.12 million, and was built in 1972.