The <a href="https://en.wikipedia.org/wiki/Twin_Peaks_Tunnel" id="mwsA" rel="mw:WikiLink" title="Twin Peaks Tunnel">Twin Peaks Tunnel</a> in <a href="https://en.wikipedia.org/wiki/San_Francisco" id="mwsQ" rel="mw:WikiLink" title="San Francisco">San Francisco</a>, <a href="https://en.wikipedia.org/wiki/California" id="mwsg" rel="mw:WikiLink" title="California">California</a> begins service as the longest <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Streetcar" id="mwsw" rel="mw:WikiLink" title="Streetcar">streetcar</a> tunnel in the world at <span about="#mwt59" data-mw='{"parts":[{"template":{"target":{"wt":"convert","href":"./Template:Convert"},"params":{"1":{"wt":"11,920"},"2":{"wt":"ft"},"3":{"wt":"m"},"abbr":{"wt":"off"},"sp":{"wt":"us"}},"i":0}}]}' id="mwtA" typeof="mw:Transclusion">11,920 feet (3,630 meters)</span> long.