An archived snapshot of a page from a defunct crowdsourced website says this began as a three-story building erected in 1929-1930, then was expanded and renovated in 1950, 1963, and 1973. I found other online sources that flatly state that it was completed in 1973 or in 1976.
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In downtown Kansas City, Missouri, on March 27th, 2022, the AT&T Long Lines Building, a/k/a the AT&T Longlines Building, a/k/a the AT&T Toll Building, a/k/a the Southwestern Bell Telephone Building, at 1425 Oak St, the northeast corner of Oak Street and Truman Road, as viewed across Interstate 670 from the southwest corner of Truman Road and McGee Street.
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Getty Thesaurus of Geographic Names terms:
• Jackson (county) (2001208)
• Kansas City (7013820)
Art & Architecture Thesaurus terms:
• beige (color) (300266234)
• brick (clay material) (300010463)
• logos (300028715)
• masonry veneer (300444225)
• skyscrapers (300004809)
• telephone exchanges (300005416)
• traffic signals (300003915)
• traffic signs (300211849)
Wikidata items:
• 27 March 2022 (Q69306379)
• 1970s in architecture (Q17173162)
• arrow (Q1139519)
• AT&T (Q35476)
• Downtown Kansas City (Q2944777)
• gantry (Q2235510)
• highway shield (Q5759965)
• Interstate 70 (Q94632)
• Interstate 670 (Q2453708)
• Interstate Highway System (Q94247)
• Kansas City-Overland Park-Kansas City, MO-KS Combined Statistical Area (Q111496508)
• March 27 (Q2457)
• March 2022 (Q61312974)
• Southwestern Bell (Q3301294)
• Treaty with the Osage, 1825 (Q7105525)
• Truman Road (Q7847730)
• United States Numbered Highway System (Q408192)
• U.S. Route 24 (Q408147)
• U.S. Route 40 (Q409496)
Library of Congress Subject Headings:
• Telephone stations (sh85133431)