There were so many Apollo Missions, and they landed on the moon (so they say). When astronauts came back to Earth from the moon, they brought Moon rock samples. Where are these moon rocks/samples now, and where can we see them?
It's well-explained on NASA'a web site ... http://curator.jsc.nasa.gov/Lunar/index.cfm
About 380 kg of rocks and soil were brought back.
Note that ...
"The lunar sample building at Johnson Space Center is the chief repository for the Apollo samples."
About three hundred moon rocks were given as gifts by the US to cities and countries around the world, and you can easily find that list, and hence go see them all. (More fun than PokemonGo!)
You can usually very easily see one at the local "national museum" in your country. I've seen maybe five all over the world at the places listed there.
It seems that at least 100 have gone missing!
There are a few moon rocks in the wild and there were cases of theft - they would be worth millions of bucks ... TV show about that.