I learned that the reason so many people with roots in the south or midwest have an ancestor who fought at Shiloh, is that there were just so many soldiers there: 110,000.
It was one of the earliest of the larger battles (April 1862), and one of the bloodiest. In just two days there were almost 24,000 casualties (more than in all previous American wars combined).1,2
Shiloh is said to be the best preserved battlefield of the Civil War3,4.
This is where the shooting started, in Fraley Field. A Union patrol encountered advancing Confederate pickets. The whole attack was a surprise, but this engagement gave the unfortified Union camps at least a little warning.
That marker in the middle of the far field looks far away, until you think about someone standing over there shooting at you, at which point it seems a lot closer.
Replica of the Shiloh meeting house. Sherman's division was here at the beginning of the battle, and the original church was used as different headquarters on different days. (The Confederates won the first day, but the Union was reinforced overnight and won the second day.)
The peach orchard was in bloom during the battle. Petals cut by flying bullets reminded observers of falling snow. In the end there were no petals left on the trees. (These newly replanted peach trees apparently had somewhat of a deer problem.)
One end of the sunken road. (Not really so sunken anymore after 145 years.) It leads to the Hornets' Nest, a thicket where the fighting was particularly fierce.
This was called "The Bloody Pond" after so many wounded men and horses gathered there, that the water became red with their blood.
1My great-great-grandfather was among them. His records are incomplete, but his wound was severe enough that he was discharged from the army less than a month after Shiloh.
2That's more than our casualties of the Revolutionary War, the War of 1812, and the Mexican-American War all put together. And Shiloh was only the worst battle up to that point. It got even worse later on.
3Shelby Foote said that. (I am obliged to make a joke about this being a Foote note.)
4Lots of people here still call it the War Between the States. A few people call it the War of Northern Aggression. If they are not kidding, those are usually the kind of people you want to watch out for.