Ulysses S. Grant wanted complete control of the Mississippi River. He wanted this so he could receive important supplies. In doing this, he would deprive the Confederates their supplies. The only Confederate stronghold that was preventing Grant from his goal was the city of Vicksbug.
After multiple unsuccessful attacks on VIcksburg, Grant decided to host a siege on it.
Fought in a 12-foot deep crater
So then, the 47 day siege started. The Confederate's rations quickly shortened. And with the additional bombarding of the Navy ships, made the Confederates miserable. Some tried to make tunnels to shelter them from heavy shelling from the Union.
!! Union Victory !!
Grant commanded his troops to dig tunnels and place explosives. The explosives caused a large explosion.
Both sides fought inside the crater created by the explosions for over 20 hours. But the Union was exhausted and retreated back to their lines.
Soon after, the Confederates surrender and the Union won.