Penobscot Building
Penobscot Building seen from Campus Martius Park in 2025
Interactive map of Penobscot Building
Alternative names	City National Bank Building Penobscot Building - 47 Tower
General information
Type	Commercial offices
Location	645 Griswold Street Detroit,Michigan
Coordinates	42°19′49″N83°02′51″W / 42.33041°N 83.0475°W /42.33041; -83.0475
Construction started	1927
Completed	1928
Owner	Triple Group Of Companies
Management	Triple Properties Detroit
Height
Antenna spire	202.4 m (664 ft)
Roof	172.2 m (565 ft)
Top floor	159.4 m (523 ft)
Technical details
Floor count	above ground: 47 below ground: 2
Floor area	1,258,900 sq ft (116,960 m2)
Lifts/elevators	25
Design and construction
Architects	Wirt C. Rowland Smith, Hinchman & Grylls Donaldson and Meier
Greater Penobscot Building
U.S. Historic district Contributing property
Architectural style	Art Deco
Part of	Detroit Financial District (ID09001067)
Designated CP	December 14, 2009
References
[1][2][3]

TheGreater Penobscot Building, commonly known as thePenobscot Building, is aclass-A office tower inDowntown Detroit,Michigan.^[4] Constructed in 1928, theArt Deco building is located in the heart of theDetroit Financial District. The Penobscot is a hub for the city'swirelessInternet zone andfiber-optic network.

Upon completion, the Penobscot Building was the eighth-tallest building in the world, the fourth-tallest in the United States^[5] and the tallest outside ofNew York andChicago.^[6][7] Rising 566 feet (173 m), the 47-story Penobscot was the tallest building in Michigan from its completion in 1928 until construction of theRenaissance Center hotel tower in 1977.Ally Detroit Center (formerly One Detroit Center) surpassed the Penobscot as thetallest office building in Detroit upon its completion in 1993. The framing elevation drawing of this building shows a height of 562.166 ft (171.348 m) to the highest roof, approximately 565.75 ft (172.44 m) to the parapet wall around the roof, and 654.166 ft (199.390 m) to the top of the warning beacon atop the antenna.

The Penobscot has 45 above-ground floors and two basement levels, for a total floor count of 47. Although the Penobscot Building has more floors thanAlly Detroit Center (45 above-ground floors compared to 43 for Ally Detroit Center), the floors andspires of One Detroit are taller, with its roof sitting roughly 60 ft (18 m) higher than that of the Penobscot.

The building is named for the Penobscot River in Maine. The building was named by Simon J. Murphy, President of the Simon J. Murphy Company. Murphy named the building from his association with lumbering in the Maine woods and on the Penobscot River in Maine.^[8] Motifs in art deco style ornamentation is used on the exterior and the interiors. The following version of the choice of the name of the building is found in an undated publication believed to have been published concurrent with the building's dedication in 1928:

An intimation of theSimon J. Murphy Sr. family's early history, together with the expression of genuine sentiment regarding the beginnings of the Murphy fortune, is contained in the name of the Greater Penobscot Building...... Long before the Civil War days, Simon J. Murphy and his partner, then two lads who had grown up in the Maine woods obtained their first employment in one of the logging camps along the Penobscot River - a stream named for the powerful tribe of Penobscot Indians.

The architectWirt C. Rowland, of the prominentSmith Hinchman & Grylls firm based in Detroit, designed the Penobscot in an elaborateArt Deco style in 1928. Clad inIndiana Limestone with agranite base, it rises like a sheer cliff for thirty stories, then has a series of setbacks culminating in a redneonbeacon tower. Like many of the city's otherRoaring Twenties buildings, it displays Art Deco influences, including its "H" shape (designed to allow maximum sunlight into the building) and the sculptural setbacks that cause the upper floors to progressively "erode".

The opulent Penobscot is one of many buildings in Detroit that featuresarchitectural sculpture byCorrado Parducci. The ornamentation includesAmerican Indian motifs, particularly in the entrance archway and in metalwork found in the lobby. At night, the building's upper floors are lit in floodlight fashion, topped with a red sphere.

The building's architect, Wirt C. Rowland, also designed other Detroit skyscrapers, such as theGuardian Building and theBuhl Building, in the same decade.

The tower is also connected to two older and smaller buildings, the 1905Penobscot Building and thePenobscot Building Annex (1916). Together, the buildings comprise thePenobscot Block, located at Griswold Street and West Fort Street. TheGreater Penobscot was the last portion of the complex to be developed.

On holidays, both the Penobscot Building and the nearbyOne Woodward Avenue light-up for the night, with red, white and blue forIndependence Day andCanada Day; and red, white and green for theChristmas season. In addition, during the Christmas season, the Penobscot Building's radio broadcast tower is illuminated bright gold, to resemble a giant glowingChristmas tree topped with a flashing redbeacon. The Penobscot Building has become a souvenir item along with other Detroit skyscrapers.^[9]

The first televisions in Michigan were sold in the retail space on the Griswold level of this building.^{[citation needed]}

For a period of time in the late 1970s and early 1980s, it was renamed theCity National Bank Building, after its major tenant. When City National was acquired by another bank and renamed, the historic Penobscot name was revived.

The Penobscot Building is acontributing property in theDetroit Financial Historic District, and on theNational Register of Historic Places.

• The Caucus Club, a restaurant known for hosting influential business officials, was located in Penobscot from 1952 until 2012. On October 4, 2012, the restaurant announced that it would close by the end of that month. Early in her career,Barbra Streisand appeared as one of the lounge singers at the Caucus Club in 1961. Caucus Club reopened under new ownership in 2017, after an extensive renovation.^[10]
• The tower apex once had "CNB" signs for a local bank that was formerly headquartered in the Penobscot Building.^[11]
• For approximately 20 years ending in 2009, the building was home to radio stationWJLB and its well-known 80s DJ,The Electrifying Mojo, who broadcast hisnightly visits over Detroit from his 'Mothership'. The Electrifying Mojo is credited with exposing manyDetroit techno musicians to new audiences through his broadcasts.^{[citation needed]}
• The Smart Detroit Conference Center occupies space on the 13th floor, and includes Class A conference, meeting, or convention space.^{[citation needed]}
• TheWayne County Friend of the Court occupies floors between the sub-basement and eighth floor, making it the current largest tenant of the building.^{[citation needed]}

In May 2012, the Penobscot Building was sold for $5 million to theToronto-based real estate company, Triple Properties Detroit.^[12][13] The building has since incurred numerous fines and code violations from the city of Detroit.^{[14][15][16][17][18]}

• Penobscot Block —the complex

• The Penobscot Building —the oldest
• Penobscot Building Annex —access connected

• Buhl Building
• Detroit Financial District
• Guardian Building
• List of tallest buildings in Detroit
• National Register of Historic Places listings in Detroit, Michigan

• Greater Penobscot Building: Fort and Griswold Streets, Detroit. c. 1928. (booklet)
• Hill, Eric J. & John Gallagher (2002).AIA Detroit: The American Institute of Architects Guide to Detroit Architecture. Wayne State University Press.ISBN 978-0-8143-3120-0.
• Kvaran, Einar Einarsson,Shadowing Parducci, unpublished manuscript, Detroit.
• Meyer, Katherine Mattingly and Martin C.P. McElroy with Introduction by W. Hawkins Ferry, Hon A.I.A. (1980).Detroit Architecture A.I.A. Guide Revised Edition. Wayne State University Press.ISBN 978-0-8143-1651-1.{{cite book}}: CS1 maint: multiple names: authors list (link)
• Sharoff, Robert (2005).American City: Detroit Architecture. Wayne State University Press.ISBN 978-0-8143-3270-2.
• Savage, Rebecca Binno & Greg Kowalski (2004).Art Deco in Detroit (Images of America). Arcadia.ISBN 978-1-4396-1485-3.
• Sobocinski, Melanie Grunow (2005).Detroit and Rome: building on the past. Regents of the University of Michigan.ISBN 978-0-9336-9109-4.

• Media related toPenobscot Building at Wikimedia Commons
• Official Penobscot Building website
• Caucus Club website
• Article from the Detroit Area Art Deco SocietyArchived 2008-10-29 at theWayback Machine

• Art Deco skyscrapers
• Downtown Detroit
• Skyscraper office buildings in Detroit
• Commercial buildings completed in 1928
• Historic district contributing properties in Michigan
• National Register of Historic Places in Detroit
• Office buildings on the National Register of Historic Places in Michigan
• 1928 establishments in Michigan
• 1928 sculptures
• Buildings with sculpture by Corrado Parducci
• Outdoor sculptures in Michigan
• 1920s architecture in the United States
• Art Deco hotels
• Art Deco architecture in Michigan

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