### Instruction: What is the tallest building in the city of San Francisco?
### Input: Salesforce Tower, formerly known as Transbay Tower, is a 61-story skyscraper at 415 Mission Street, between First and Fremont Street, in the South of Market district of downtown San Francisco. Its main tenant is Salesforce, a cloud-based software company. The building is 1,070 feet (326 m) tall, with a top roof height of 970 feet (296 m).
### Response: Salesforce Tower is a 61-story skyscraper at 415 Mission Street, between First and Fremont Street, in the South of Market district of downtown San Francisco. The building is 1,070 feet (326 m) tall, with a top roof height of 970 feet (296 m).