TESTING

What you are looking at is more than just a concrete block by the water; it's a piece of hidden history that tells a fascinating story of American wartime ingenuity and the surprising role of balloons. This concrete mass is actually the base of what was once a large "masthouse" crane, used by the Marine Officer's Training Academy during World War II.

During the war, this location was a bustling training ground where candidates learned the vital skills of loading and unloading cargo from ships. Ships were particularly vulnerable to enemy attacks while docked, making the secure transfer of goods a critical concern. To combat this threat, an unusual defense mechanism was employed: barrage balloons. These large, blimp-shaped balloons, like the one you see depicted on the interpretative sign, were tethered to the ground and floated high in the air, creating a physical barrier with their long cables. The idea was to prevent low-flying enemy aircraft from approaching the ships, either by forcing them to fly higher into the range of anti-aircraft guns or by risking entanglement in the cables. It was an innovative, if somewhat quirky, solution to a serious problem.

The sign also points out the "cleats" – the metal attachments still visible on the concrete block. These were used to tie down the massive fabric balloons, ensuring they stayed put despite winds and maneuvers. It's a testament to the scale of these operations that such robust attachments were needed. If you look closely at the photos on the sign, you can get a better sense of how these impressive balloons were deployed and managed. They were a common sight in wartime ports, a silent sentinel protecting vital supply lines. This seemingly simple concrete structure is a direct link to a time when Alameda played a critical role in supporting the war effort, training the next generation of marine officers and pioneering unusual defense strategies.