Building Salesforce Tower without a single tenant lined up was an incredible risk for the City of San Francisco, Boston Properties and Hines. Now that the tower has been topped off, the building is nearly 75% leased (including the company from which it now takes its name) and is fast becoming an iconic feature of San Francisco’s skyline.

“There is almost no point in San Francisco where you can be today without seeing the tower,” San Francisco supervisor Jane Kim said. “This is truly changing the skyline of San Francisco.”

The 1,070-foot tower is the tallest tower west of the Mississippi and offers more than 1M SF of office space.

When the building was first conceived, Kim said many developers told her it was too big. It also was risky to commit to such a project at the tail end of the economic downturn, she said. But the project paid off. The tower created thousands of jobs, 25% of which were for San Francisco residents, according to Kim.

Salesforce Tower also allowed for the building of the Transbay Terminal, which will offer a rooftop park and connections for several regional transit agencies.

Hines senior managing director Paul Paradis said Salesforce Tower is now Hines’ tallest building across its portfolio, which spans 189 cities around the world.

The tower offers expansive column-free space that allows tenants to create any kind of workspace. The foundation reaches 300 feet below grade and is firmly in bedrock. The building also has a LEED Platinum designation. Other pre-leased tenants besides Salesforce include Bain & Co., CBRE and Accenture, Paradis said.

The tower's top floor will not be used as an office, according to Salesforce founder, chairman and CEO Marc Benioff. The 61st floor will become the Ohana Floor, an open space where Salesforce employees will collaborate or hold meetings. On nights and weekends, the space will be available to the community for nonprofits and others to use without charge.

Benioff said with Salesforce Tower, Salesforce West (50 Fremont) and Salesforce East (350 Mission), the company will have 10,000 people working in the area. He said Saleforce is among the fastest-growing companies. It employs 25,000 people and expects to employ 30,000 by the end of the year.

San Francisco Mayor Ed Lee, Pelli Clarke Pelli senior principal Fred Clarke and Boston Properties executive vice president and regional manager Bob Pester also spoke during the topping off ceremony.

Check out the view from the rooftop of the tallest tower west of Chicago below.