General Archives of the Indies, Sevilla

The Spanish realized pretty darn quickly that the New World was a monumental discovery, a real game changer for the whole planet.  At some point not too long after Cristóbal Colón made his way back to Europe the Spanish were all over getting their men there, getting some colonies established, looking for riches to bring home, and bringing some religion over to get the native people started on what they thought was the path to God.

There was much correspondence that went along with the discoveries that were made.  The king had to be updated on all that was happening.  Once the Spanish moved from discovery to conquer mode, and they had sent Cortez in, they needed to keep the kingdom informed of what they were doing, what treasures they were finding, and keeping ledgers of what was being shipped back to Spain.  It was a prodigious amount of silver and gold, which was largely mined by native slave labor under the direction of the Spanish Conquistadors.  It is said in Potosi, Bolivia that enough silver left the Bolivian mountain and went to Spain to build a bridge from Spain to Bolivia.  I don't know about that, but the river that runs between Argentina and Uroguay, where much of the silver left South America, is called the Rio Plata, or the Silver River.

Cortes was a ruthless man who committed many atrocities, but the silver he helped bring out of the New World changed the currency and balance of trade of the entire world.  Spain was in her hey day.

It is possible the Spanish didn't realize it then, but by the mid-19th century they definitely knew--so what they did was amass all of the paper trail related to the discovery and what happened thereafter in one place--which initially was in Madrid, but was later moved to this massive and imposing building in Sevilla, across from the Cathedral that is Cristóbal Colón's ultimate burial ground, and near the Real Alcazar--inother words centrally located in the ancient part of the city.  There is not a lot to see there, but it is a free building to enter, and for an American whose family has been in the New World since the 17th century, it feels relevant.