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A new interactive study released by the Council on Tall Buildings and Urban Habitat (CTBUH) has illustrated a timeline depicting the frequently-changing record for world's tallest observation deck. Entitled Tall Buildings in Numbers – The World’s Highest Observation Decks, the study covers the 75 tallest structures from around the globe containing observation decks or viewing platforms.
Spanning generations of tall building construction, the timeline pictured above covers the progressing of the tallest observation deck in the world, from the 152-metre viewing platform near the top of the 169-metre Washington Monument in Washington D.C., up to the 634-metre observation deck soon to take shape at the under-construction, 1,000-metre Kingdom Tower in Jeddah, currently scheduled for 2018 completion.
Three smaller timelines depict the progression of observation deck heights in three cities known for building tall; New York City, Chicago, and Shanghai. The timeline for New York starts on the 282.5-metre Bank of Manhattan Building, which features a 254.8-metre observation deck that opened in 1930. This height was surpassed just one year later by the iconic Empire State Building, which held the title until the 1975 completion of Two World Trade Center and its 415-metre observation deck. The building's 2001 destruction in a terrorist attack temporarily brought the title of tallest observation deck in New York back to previous record-holder, The Empire State Building, which would eventually be surpassed again in 2014 by a rebuilt One World Trade Center featuring a 386.5-metre observation deck.
The study not only highlights the heights of the 75 tallest observation decks, but also the main function of the structures they occupy. At 40%, the bulk of the structures highlighted in this study are designated as mixed-use, while 28% are classified as office towers. 20% of the structures in the study are telecommunications and observation towers, while 9% are residential and 3% are hotels.
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