The story
Read it all →How San Juan came to be
From Wikipedia’s history of San Juan.
The community was organized in 1909, in part, due to the efforts of John Closner.
Text from Wikipedia, licensed CC BY-SA 4.0.
DHistory
History · San Juan
San Juan’s post office opened in 1909
More historic than 5% of U.S. towns · #584 of 642 in Texas. What drives it
Most of San Juan was built recently: 0.3% of its homes predate 1940 and the median home dates from 1999. Below: 6 old photos and papers, maps from 1914 on, and the census since 1920.
1909first post office
0on the National Register
0.3%homes built before 1940
6old photos & papers
Quick answers
How San Juan began
When was San Juan founded?
1909
The San Juan post office opened in 1909, the earliest record of the town by name.
First census: 1,203 in 19202020 census: 35,294117 years
How historic is San Juan?
D
What drives the grade ↓More historic than 5% of U.S. towns, on its age, its old homes and the National Register.
Founding year: the first San Juan post office (Blevins & Helbock, CC0).The full story ↓
History grade
What drives San Juan’s History grade
On its age, its old homes and the National Register, San Juan is more historic than 5% of U.S. towns, #584 of 642 in Texas. Its National Register listings hold the grade up; its share of homes from before 1940 pulls it down.
D
HistoryA character grade: shown, never part of San Juan’s overall grade.
Founding era1909, from the first post office: founded 1900–1944, an older era than 9% of U.S. townsDHomes built before 19400.3% of homes (±0.3) · typical TX town 1.6% · U.S. 8.4%DNational RegisterNo listings counted · typical TX town 0.0 per 10,000 · U.S. 2.4C
All U.S. towns we grade (21,289)Ahead of 5%
NewerOlder
Texas towns of 2,500+ (642)Ahead of 9%
Few Texas towns list much on the Register (a typical Texas town has 0.0 per 10,000 residents, the U.S. 2.4), so San Juan’s 0.0 sits below most of its state (34% of Texas towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
How sure. Graded on any two of the three inputs instead, the letter would range from D− to D. The pre-1940 share (±0.3 points) is firm at this size. The founding year is the first post office, not a stated founding date.
Founding year: the first post office (other dates in Quick answers). Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
What stands out about San Juan’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
★ What stands out · Places that used to be
Old corners, places now gone and burying grounds
San Juan’s post office has been open since 1909.
Hamlets and corners on the map
Arco Iris Number 2 ColoniaArguello ColoniaArguello Number 2 ColoniaAzteca Acres ColoniaBar Number 4 ColoniaBarrios Number 2 ColoniaCitriana Village ColoniaEldora Gardens ColoniaEldora Rd-FM 1426 ColoniaEncino Heights ColoniaFM 1426-Minnesota Road ColoniaLantana ColoniaLas Palmas Estates ColoniaMiller Resub Lot A ColoniaMorningside Mobile Home Park ColoniaMorningsun ColoniaParadise Park ColoniaPorciones Center ColoniaPrimavera Colonia Number 1Primavera Number 2 ColoniaR S W incorporated Number 1 ColoniaRed Barn ColoniaRomo ColoniaSan Juan East Colonia
Gone or out of use
Pharr Gas Fieldoilfield
1cemetery inside San Juan
San Juan
US Post Offices dataset (Blevins & Helbock, CC0). Places and cemeteries from the USGS Geographic Names Information System (2021).
On the map
San Juan on the map, 1914 to 1983
Every edition of the U.S. Geological Survey’s map of San Juan. Tap a year, or press play to watch the town change.
1914San Juan sheet · 1:62,500U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of San Juan.
Timeline
San Juan, 1909 to 1939
Woven from the archive, old maps, post office records, the National Register and the people born here.
By decade
San Juan, decade by decade
One decade in the archive so far: the 1930s. Scroll each row; tap a photo for its story.
1930s6 items
1939
1939
1939
1939
19391940s–1990snothing yet
Nothing in the archives for these yearsWeddings on Main Street, storms, parades, school pictures, the old store. If it’s in your family album, it belongs here.
Add from your albumEvery building
San Juan, building by building, 1925
Fire insurance maps drew every building, what it was made of and what it was used for, so insurers could price the risk of fire. Pick a sheet.
1925Sheet 1 of 2BrickWoodStone
Sanborn Map Company, via the Library of Congress. Editions published in 1930 or earlier, which are in the public domain.
Then & now
Stand where they stood
No then-and-now pairs yet. Take a photo from the same spot as an old one and they appear here side by side.
Retake this viewSign, 1939
Find the spot, match the angle, and add your photo. It becomes the first then-and-now pair on San Juan’s page.
Retake this view · +15People over time
San Juan, census by census
Grew from 1,203 people in 1920 to 35,294 in 2020, more than tenfold.
11 censuses, 1920–2020.
U.S. Census Bureau decennial counts, from the census table on San Juan’s Wikipedia page.
Help out
Finish San Juan’s story
Most archives stop around 1920. The photos from after that are in family albums, not libraries.
Decades since 1900 with photos
00s10s20s30s40s50s60s70s80s90s
1 of 10 decades. The empty ones are waiting for someone’s album.Stories next door
History across the town line
Each neighbor’s History grade, on the same three inputs.
Questions about San Juan’s history
What year was San Juan founded?
The San Juan post office opened in 1909, the earliest record of the town by name (U.S. post office records).
How does San Juan rank for history?
San Juan is more historic than 5% of U.S. towns, #584 of 642 in Texas. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
How old are the homes in San Juan?
0.3% of San Juan’s homes were built before 1940 (Census estimate), against a typical 1.6% for a Texas town; the median home was built in 1999.
Memory lane
What the archives can’t tell you, neighbors can.
Start a conversation
Sources
Where this page comes from
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From the Library of Congress (6), Wikipedia, U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the US Post Offices dataset (Blevins & Helbock), the USGS Geographic Names Information System and Sanborn fire insurance maps (Library of Congress). Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.