Designed as a way to give shape to a swelling metropolis, officials approved the zonification of Guatemala City — often Guate (pronounced "wah-te") to locals — in 1952, according to the municipality's website. Two decades later, as the city grew, leaders voted on a resolution laying out the boundaries of zones 1 through 25. No explanation was forthcoming on why three zones, including 20, were missing.

In a sprawling city such as Guate, zones are a quick way to give people a rough estimate of the spot you're talking about. "¿Zona?" taxi drivers often ask as you hop in. The zones start near the city's center, with Zone 1, the oldest part of the capital, home to the national palace and the central market. Then they spiral out counterclockwise.

It's kind of a mirror image of Paris' 20 arrondissements, which spiral out clockwise. (None of them, however, is missing.)

"Como un caracol," many Guatemalans say. "Like a snail."

On top of the numerical zones, the city's Zone 10 is also called Zona Viva — the "lively zone" jammed with hotels and bars and nightclubs — and the poorest and most dangerous spots get branded una zona roja (a red zone).

How many zones exist depends on whom you ask. WikiTravel, an online travel guide, says 21, and Wikipedia puts the number at 22, saying they go up to 25, but that zones 20, 22 and 23 are missing. Nuestro Diario, a newspaper in Guatemala City, offers a post saying that there are 25 zones but that a few them technically belong to other municipalities.

The municipality's website skips the same three as Wikipedia and links to each zone's Facebook page.

People use the pages to post pictures of a tan chow chow named Sony who went missing from Zone 19 or to tell their leaders in Zone 5 about annoying potholes. There's a food truck event in Zone 1 — the bustling center with a reputation for both its pickpockets and its gentrifying pockets — and there's serious flooding on 9th Avenue in Zone 7, one of the city's most dangerous.

In the zona whose name often lands in headlines like "Women's bodies found in a ravine in Zone 18," the Facebook page carries no mention of violence. Instead, there are pictures of the new skate park in the zone's Paraíso II neighborhood — second paradise, it's called. In rectangle-shaped Zone 19, sometimes called "the island" because it floats separate from the rest of the city, someone posts about traffic congestion.

The most infamous, though, is the missing Zone 20.