By: Caroline Chen

A 15th-century Christopher Columbus letter is finally back in Italy, after it disappeared from a Venice library decades ago .

Italy and the US are on good terms, so the US had agreed to try to find it in the US. U.S. Immigration and Customs Enforcement (ICE) announced that they tracked the letter to Rome after a multifaceted international investigation.

“This is the fourth original edition of this letter stolen over the past decades and we could not be happier to return it,” Deputy Director Patrick Lechleitner said .

Columbus had written this in 1493 to Spain’s king Ferdinand and queen Isabella about what he found in the Americas. The letter was sent to Rome to be copied and written in latin. It appeared in many libraries across europe.

This particular letter is the most valuable of all the letters that were found in the last few years because it’s a copy of the first version with a value more than 1.3 million.

U.S. met with Italian officials met in Rome this week to return the letter, which is in the form of a slender hardcover booklet.