Boston Properties, one of the largest office space developers in the U.S., has teamed up with two Bay Area firms on a planned 1.1 million-square-foot office campus near San Jose's Diridon Station and search giant Google's future campus in the heart of the city.

Boston Properties said Wednesday that it has entered into a 65-year ground lease agreement with San Francisco-based TMG Partners and San Jose-based Valley Oak Partners for the site at 440 W. Julian St. known as Platform 16. Financial terms of the deal were not disclosed.

TMG and Valley Oak last year secured final city approvals for the project.

“At the site of one of the biggest technology hubs in the country, Platform 16 will help companies attract and retain the best and brightest minds to the area by offering easy access to public transportation, housing, culture, food and entertainment in the heart of San Jose," Boston Properties Executive Vice President Bob Pester said in a statement.

The 5.4-acre project is slated to include three office buildings, designed by New York City-based architecture firm Kohn Pedersen Fox Associates.

The developers emphasized that the project will feature "large floorplates" ranging from 25,000 to 90,000 square feet. The buildings will have 15-foot floor-to-floor heights, 16 outdoor terraces, indoor and outdoor workspaces and amenities including a fitness and wellness facility and conference center.

“TMG and Boston Properties share the vision of a modern office campus that addresses the top priorities of today’s growing companies: a location uniquely transit-accessible, access to affordable housing with San Jose the number one housing-to-jobs ratio in the Bay Area, and a facility that promotes collaboration and efficiency through large floorplates and multiple outdoor spaces,” Matt Field, TMG's chief investment officer, said in a statement. “The building’s location will also allow employees to enjoy an exciting urban environment with the adjacent SAP Center, San Pedro Market, and the wide variety of cultural, culinary, and entertainment experiences in downtown San Jose.”

The developers said they expect demolition to begin this spring and to break ground this summer, with an estimated completion date "as early as 2021." Boston Properties will have a one-year option in February 2020 to acquire the land at a fixed cost, it said.

Sherman Chan, Mark Schmidt, Mike Charters and Will Schmidt of CBRE are marketing the project for lease on behalf of Boston Properties and TMG.

"This planned development will help bring thousands of jobs into our city center with easy access to public transit, and include a number of public space improvements that will help connect the Guadalupe River Park to Platform 16 and the rest of the Diridon Station area," San Jose Mayor Sam Liccardo said in a statement.

The Platform 16 project is adjacent to Alphabet Inc.-owned Google's plans to build a sprawling, transit-connected urban campus in San Jose for as many as 20,000 workers. Those plans, which are still in the early stages, moved forward last year when the city agreed to sell a spate of publicly owned parcels near downtown to the company for almost $100 million.