Port Isabel’s post office opened in 1930, and 1 of its places is on the National Register
More historic than 16% of U.S. towns · #382 of 642 in Texas. What drives it
Most of Port Isabel was built recently: 0.0% of its homes predate 1940 and the median home dates from 1982. Its Register listing is the Point Isabel Lighthouse. Below: 5 old photos and papers and maps from 1929 on.
From Port Isabel’s archive · credits on each photo
Quick answers
How Port Isabel began
When was Port Isabel founded?
1930
The Port Isabel post office opened in 1930, the earliest record of the town by name. Two smaller post offices, Point Isabel (1845) and Brazos Santiago (1849), opened inside today’s city and later closed.
2020 census: 5,02896 years
How historic is Port Isabel?
C−
More historic than 16% of U.S. towns, on its age, its old homes and the National Register.
Founding year: the first Port Isabel post office (Blevins & Helbock, CC0).The full story ↓
History grade
What drives Port Isabel’s History grade
On its age, its old homes and the National Register, Port Isabel is more historic than 16% of U.S. towns, #382 of 642 in Texas. Its National Register listings hold the grade up; its share of homes from before 1940 pulls it down.
C−
HistoryA character grade: shown, never part of Port Isabel’s overall grade.
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 Port Isabel’s 2.0 sits above most of its state (75% of Texas towns have fewer) while its 1 listings outnumber those of 51% of U.S. towns.
How sure. Graded on any two of the three inputs instead, the letter would range from D− to C. The pre-1940 share (±0.8 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 Port Isabel’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Port Isabel is named after Queen Isabella of Spain, though it was originally known by Spanish colonial settlers as El Frontón (referring to a wall-like cliff extending into the bay). Over time, the area became known as La Punta de Isabela or Point Isabel derived from the Potrero de Santa Isabela land grant. When it was incorporated as a city in 1928, the name was formally updated to Port Isabel
Established as a town after the Mexican War of Independence, Port Isabel became an important cotton-exporting port before the American Civil War. The harbor, town and lighthouse all were fought over and exchanged hands during the Civil War.
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.
The Port Isabel post office opened in 1930, the earliest record of the town by name (U.S. post office records).
How does Port Isabel rank for history?
Port Isabel is more historic than 16% of U.S. towns, #382 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.
What is on the National Register in Port Isabel?
One place: the Point Isabel Lighthouse (listed 1976).
How old are the homes in Port Isabel?
0.0% of Port Isabel’s homes were built before 1940 (Census estimate), against a typical 1.6% for a Texas town; the median home was built in 1982.
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 Wikimedia Commons (2), the Library of Congress (3), Wikidata (1), the National Register of Historic Places (1), Wikipedia, Wikidata and Wikipedia for famous people, U.S. Geological Survey historical maps, the US Post Offices dataset (Blevins & Helbock) and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
1864
1923
