Some 15 years ago, Andrew Carroll heard the story: During the Civil War, Edwin Booth, brother of Lincoln assassin John Wilkes Booth, saved the life of Lincoln's son Robert at a New Jersey train station.
Intrigued, Carroll started digging. He not only confirmed the story but visited where it occurred. What bothered him was that the story and the location are unknown to most people.
It was the jumping-off point for "Here Is Where: Discovering America's Great Forgotten History" (Crown Archetype), in which Carroll visits more than 40 historical sites that have affected almost all of us, yet we know nothing about.
"Over the years I came across all these amazing stories," he said, "and I thought there had to be a book there."
The book is thick with great stories. There's Philo Farnsworth, who at 14 came up with the concept for television while plowing a potato field in Rigby, Idaho. There's the USDA lab in Peoria, Ill., where penicillin was mass produced in the run-up to World War II. (How the right mold to produce the drug in mass quantities was discovered is an amazing story in itself.) There's famed Prohibition-era federal agent Richard "Two Gun" Hart, who was Al Capone's brother.
Each location Carroll visited not only is historically important but also ties in to a larger story: invention, medicine, civil rights, space exploration, women's rights and more.
The other thing they have in common is that all these locations are unmarked.
"It is this whole concept that these places are right before our eyes, and somehow they get overlooked," he said.
Carroll is touring the country and raising money for markers to note the people and events in the book. Go to hereiswhere.org to check his itinerary. He also explains how people can uncover stories of their own.
"Studying history and traveling are very similar," he said. "You're learning things, gaining that sense of awe we had when we were younger."