Yup.<p>I actually noticed this one day in Noe Valley.  You would have a block of old houses (early 1900&#x27;s) and then in the center of the block would be buildings built in the &#x27;50s or &#x27;60s.  Why is that?<p>This is a nice zoomable map of SF from 1938 that shows why.  There used to be an elevated set of train tracks that ran from 27th and Dolores down to San Jose and Randall.  The rest of the tracks were at ground level.<p><a href="http:&#x2F;&#x2F;www.davidrumsey.com&#x2F;luna&#x2F;servlet&#x2F;s&#x2F;x0k3ok" rel="nofollow">http:&#x2F;&#x2F;www.davidrumsey.com&#x2F;luna&#x2F;servlet&#x2F;s&#x2F;x0k3ok</a><p>The removed the tracks and filled in the gaps with new homes.