Exploring San Francisco's Hidden Tunnels

<p>San Francisco is 49 square miles, but contains more than 1,000 miles of sewer mains, running under every block. Take a trip with Bay Curious reporter Carly Severn into the depths of the city, and discover an otherworldly cave that has reached legendary status with some urban explorers. This story first aired in 2019.</p><p><br></p><p>Additional Reading:</p> Exploring San Francisco's Hidden Tunnels (YouTube) Tunnels Under San Francisco? Inside the Dark, Dangerous World of the Sewers Read the transcript for this episode Sign up for our newsletter Enter our Sierra Nevada Brewing Company monthly trivia contest <p><br></p...