The site of one of the Civil War’s bloodiest battles, the Vicksburg National Military Park was established in 1899 in order to commemorate the siege and defense of Vicksburg. Today, the park is filled with hundreds of monuments and markers, historic homes, forts, and approaches, including Thayer’s Approach. The historic tunnel was vital to the Union and, in turn, the nation as a whole; however, many are unaware of its existence.

The natural resources at Vicksburg National Military Park played a significant role in the Civil War. The consistency of the park’s soil allowed troops to dig artificial caves, which were used to provide shelter for civilians during the war, trenches, and tunnels.

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One such tunnel is Thayer’s Approach, which was dug by Union soldiers under the command of Brigadier General John M. Thayer.

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Thayer’s men tried to attack the Confederacy on May 19th and again on May 22nd; however, both attempts were unsuccessful.

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In order to attack, Union soldiers needed to advance uphill to the Confederate’s location at the top of a nearly 200’ ridge.

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This put Thayer and his men at a huge risk of being shot by sharpshooters.

Mike Talplacido/Flickr

After the second failed attempt, Union soldiers began digging a 6’ deep approach trench in order to prepare for an assault up the hill.

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Bundles of cane called fascines were used to form a roof over the tunnel. These bundles not only blocked the Confederates’ view but could actually stop bullets.

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The idea was to dig the trench close enough to the Confederate troops so that a mine could be placed under the defensive position; however, this plan never came to fruition because Vicksburg ended up surrendering shortly before Union soldiers completed the mine.

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Want to see this historic tunnel for yourself? Thayer’s Approach is located at tour stop #6 at the Vicksburg National Military Park. For more information, click here.

Robert Barnette/Flickr

Mike Talplacido/Flickr

Ken Lund/Flickr

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