Interstate 45
Interstate Highway in Texas, United States
Interstate 45 (I-45) is a major Interstate Highway located entirely within the U.S. state of Texas. While most primary Interstate routes which have numbers ending in "5" are cross-country north–south routes, I-45 is comparatively short, with the entire route located within Texas. Additionally, it has the shortest length of all the primary Interstates divisible by 5. It connects the cities of Dallas and Houston, continuing southeast from Houston to Galveston over the Galveston Causeway to the Gulf of Mexico.
I-45 replaced U.S. Highway 75 (US 75) over its entire length, although portions of US 75 remained parallel to I-45 until its elimination south of Downtown Dallas in 1987. At the south end of I-45, State Highway 87 (SH 87, formerly part of US 75) continues into downtown Galveston. The north end is at I-30 in Downtown Dallas, where US 75 used the Good-Latimer Expressway. A short continuation, known by traffic reporters as the I-45 overhead, signed as part of US 75 and also part of unsigned I-345, continues north to the merge with the current end of US 75. Traffic can use Spur 366 (better known locally as the Woodall Rodgers Freeway) to connect to I-35E at the north end of I-345.
The portion of I-45 between Downtown and Galveston is known to Houston residents as the Gulf Freeway.
Begin with the source’s own compact description: “Interstate 45” is interstate Highway in Texas, United States. The dossier treats that line as a proposition to test through Interstate, Highway and Texas, not as a finished interpretation.
Why this record matters
The phrase “interstate Highway in Texas, United States” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 1, 2026. The linked authority identifier is Q94297. Authority coordinates are 30.357, -95.484. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1987.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Interstate 45”, its source revision and the description used here.
- Expand the search: follow Interstate 45 primary sources, Interstate 45 archive and Interstate research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Interstate 45”?
- Which institution is responsible for the underlying evidence?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “Interstate 45” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.