The crazed Nazi-sympathizing gunman who killed a Canadian tourist and injured 13 others after opening fire from atop a pyramid at Mexico’s Teotihuacán ruins plotted the attack for two months – and studied an image of the tourist hotspot that was in his hotel room.

Julio César Jasso sent text messages in February, asking about staying in a hotel room between April 8 and 20, and the distance to what he described as the “Holy City,” Mexican outlet Telediario reported.

Jasso inquired about the availability of a single room at Hotel Villa Meztli – located three miles from Teotihuacán – during a conversation with hotel bosses on Feb. 17.

“What I’m interested in knowing is exactly where this is, and how far away it is from the Holy City,” he wrote in Spanish. 

The total cost of his room was 7800 pesos ($451), but Jasso had to pay 50% of that total to reserve the vacancy.

He told hotel management that the room would be booked under the name “Julio Cesar Ramirez” and sent proof of his bank transfer.

The alleged shooter messaged the hotel one week before arriving to make sure everything was in order for his stay and to confirm he could pay his balance in-person.

He stayed in a 4×4 room that had a picture depicting the scene looking out from the Pyramid of the Moon – the pyramid which he scaled – before unleashing a hail of bullets.

Investigators said he would study the picture, plotting the scene of the shooting.

Officials also discovered warped notes in the room where he penned thoughts about being superior.

Jasso visited the tourist attraction several times before Monday’s shooting, Milenio reported.

He was armed with a 1968 Smith & Wesson firearm and there were 58 rounds of unused ammunition, according to the outlet.

Chilling footage has since surfaced showing Jasso pacing back and forth, loading his gun on a platform on the ruins — once used for human sacrifice.

Witness Laura Torres told local media she saw Jasso shooting from “up on top of the pyramid” before saying “there were a lot of people, he had people as hostages.”

He shot dead a Canadian woman, while six Americans, three Colombians, one Russian, two Brazilians and one Canadian were taken to the hospital.

Jasso died of a self-inflicted gunshot wound. 

Security officials recovered a knife as well as a bizarre AI-generated image of the gunman posing with the Columbine High School shooters, coinciding with the 27th anniversary of the massacre.

Authorities additionally said they found images of Jasso performing the Nazi salute, which he’d been known to do since he was a teenager, Telediario reported. And, Adolf Hitler was born in Austria on April 20 1889.

Mexican President Claudia Sheinbaum wrote on X that she has been in touch with the Canadian Embassy and that she has instructed Mexico’s security cabinet to “thoroughly investigate” the incident. 

The Pyramid of the Moon was built between 100 and 450 C.E. — centuries before the Aztec empire — when Teotihuacán was among the largest cities in the ancient world.