Aerial view of the Union Iron Works, San Francisco, California (USA), photographed during World War I, with four-piper destroyers under construction at the Risdon Iron Works in the lower right. Four submarines and one destroyer hull in dry-dock are at the piers in the center, along with some large merchant ships. Risdon, part of Union, is to the lower right of the ink line.<br><ul><li>1: Cafeteria,</li>
<li>2: Store room,</li>
<li>3: Iron Foundry,</li>
<li>4: Brass Foundry,</li>
<li>5: Machine shop,</li>
<li>6: Pattern shop,</li>
<li>7: Erecting machine shop,</li>
<li>8: Administration building,</li>
<li>9: Power house,</li>
<li>10: office building, Government offices,</li>
<li>11: Blacksmith shop,</li>
<li>12: Bioler shop,</li>
<li>13: Joiner shop,</li>
<li>14: Joiner shop, annex with oil storage tanks underneath,</li>
<li>15: Warehouse and office building,</li>
<li>16: Pipe and copper shop,</li>
<li>17: Steel storage,</li>
<li>18: Plate shop,</li>
<li>19: Gate house,</li>
<li>20: Building slips 4&amp;5,</li>
<li>21: Building slips 1.2 &amp; 3,</li>
<li>22: Wharf #2,</li>
<li>23: Wharf #3,</li>
<li>24: Floating dock, capacity 2000 tons,</li>
<li>25: Floating dock, capacity 6500 tons,</li>
<li>26: Wharf #4,</li>
<li>27: Wharf #5,</li>
<li>S: Storage space</li>
<li>2: <b>Risdon Plant</b> shown south and east of red lines:</li>
<li>1: Copper storage,</li>
<li>2:  Oil tank,</li>
<li>3: Office building,</li>
<li>4: Office building,</li>
<li>5: Yarrow boiler shop,</li>
<li>6: Warehouse,</li>
<li>7: Power house,</li>
<li>8: Blacksmith shop,</li>
<li>9: Storehouse,</li>
<li>10: Sheet metal shop,</li>
<li>11: Sheet metal shop,</li>
<li>12: Marine machine shop,</li>
<li>13: Wharves,</li>
<li>14: Wharves,</li>
<li>15: Wharves.</li></ul>
U.S. Naval History and Heritage Command photo <a rel="nofollow" class="external text" href="https://www.history.navy.mil/content/history/nhhc/our-collections/photography/numerical-list-of-images/nhhc-series/nh-series/NH-42000/NH-42535.html">NH 42535</a>