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U.S. Roads: U.S. Highways / Mississippi Mid‑importance This article is within the scope of the U.S. Roads WikiProject, an attempt to build a comprehensive and detailed guide to state highways and other major roads in the United States. If you would like to participate, you can edit the article attached to this page, or visit the project page, where you can join the project and/or contribute to the discussion.U.S. RoadsWikipedia:WikiProject U.S. RoadsTemplate:WikiProject U.S. RoadsU.S. road transport articles Mid This article has been rated as Mid-importance on the project's importance scale. Topics   U.S. Highways   Locations   Mississippi   This article has a map. If the file has an error, please work with the Maps department to correct it. This article does not require a junction list. This article has a KML file. If the file has an error, please work with the Maps department to correct it.   United States: Arkansas / Mississippi Mid‑importance This article is within the scope of WikiProject United States, a collaborative effort to improve the coverage of topics relating to the United States of America on Wikipedia. If you would like to participate, please visit the project page, where you can join the ongoing discussions. Template Usage Articles Requested! Become a Member Project Talk Alerts United StatesWikipedia:WikiProject United StatesTemplate:WikiProject United StatesUnited States articles Mid This article has been rated as Mid-importance on the project's importance scale. This article is supported by WikiProject Arkansas (assessed as Mid-importance). This article is supported by WikiProject Mississippi (assessed as Mid-importance).

This article is completely unreferenced outside of the length, and that it's a WP:SPS. — Fredddie ™ 23:21, 20 April 2010 (UTC) reply

Why is 278 longer than its parent? 2600:1700:6180:6290:28B0:221A:EFC0:6E5B ( talk) 18:12, 4 August 2022 (UTC) reply

Because the states where US 278 runs asked AASHO/AASHTO for it to run the length that it does. Since US 78 and US 278 are both primary US Highways, I don't see any issue with the relative lengths. Imzadi 1979  → 21:06, 4 August 2022 (UTC) reply

US 278 is an auxillary route, not primary route 2600:1700:6180:6290:28B0:221A:EFC0:6E5B ( talk) 21:23, 5 August 2022 (UTC) reply

If you are reasoning by analogy with the Interstate Highway System, that analogy falls flat. AASHTO does not classify the United States Numbered Highway System the same way that the FHWA classifies the Interstates. Per AASHTO, the auxiliary routes in the USNHS are the special routes, and all of the mainline highways are primary highways, whether they have one, two or three digits in their numbers. Imzadi 1979  → 23:00, 5 August 2022 (UTC) reply