Observation deck in the context of Transparency (optics)

The original Two World Trade Center (also known as the South Tower, Tower 2, Building Two, or 2 WTC) was one of the Twin Towers in the original World Trade Center Complex in New York City. The Tower was completed and opened in 1973 at a height of 1,362 feet (415 m) to the roof, distinguishable from its twin, the North Tower (1 World Trade Center), by the absence of a television antenna. On the 107th floor of this building was a popular tourist attraction, "Top of the World Trade Center Observatories," and on the roof was an outdoor observation deck accessible to the public and a disused helipad at the center. The address of this building was 2 World Trade Center, with the WTC complex having its own ZIP code of 10048.

The South Tower was destroyed along with the North Tower in the September 11 attacks. At 9:03 a.m, seventeen minutes after its twin was hit, the South Tower was struck by United Airlines Flight 175. Although it was the second of the two skyscrapers to be hit by a hijacked airliner, it was the first to collapse, at 9:59 a.m., after burning for 56 minutes. Of the 2,977 victims killed in the attacks, around 1,000 were in the South Tower or on the ground.

The Belvedere on the Pfingstberg (German: Belvedere auf dem Pfingstberg) is a palace north of the New Garden in Potsdam, Germany, at the summit of Pfingstberg hill. It was commissioned by King Friedrich Wilhelm IV of Prussia and built between 1847 and 1863 as a viewing platform.

Because of its architecture and historical importance, the Belvedere forms part of the UNESCO World Heritage Site Palaces and Parks of Potsdam and Berlin, inscribed in 1999.

The Laboe Naval Memorial (a.k.a. Laboe Tower, German: Marine-Ehrenmal Laboe) is a memorial located in Laboe, near Kiel, in Schleswig-Holstein, Germany. Started in 1927 and completed in 1936, the monument originally commemorated the World War I war dead of the Kaiserliche Marine, with the Kriegsmarine dead of World War II being added after 1945. In 1954 it was rededicated as a memorial for the sailors of all nationalities who were lost at sea and at the same time a memorial for peaceful sailing in open seas.

The monument consists of a 72-metre-high (236 ft) tower topped by an observation deck. The deck stands a total 85 m (279 ft) above sea level. A hall of remembrance and World War II-era German submarine U-995, which houses a technical museum, both sit near the foot of the monument, and the site is a popular tourist venue. U-995 is the world's only remaining Type VII U-boat.

The Willis Tower, formerly and still commonly referred to as the Sears Tower, is a 110-story, 1,451-foot (442.3 m) skyscraper in the Loop community area of Chicago in Illinois, United States. Designed by architect Bruce Graham and engineer Fazlur Rahman Khan of Skidmore, Owings & Merrill (SOM), it opened in 1973 as the world's tallest building, a title that it held for nearly 25 years. It is the third-tallest building in the Western Hemisphere, as well as the 23rd-tallest in the world. Each year, more than 1.7 million people visit the Skydeck, the highest observation deck in the United States, making it one of Chicago's most popular tourist destinations. Due to its height and location, the tower is visible from a great distance. The building has appeared in numerous films and television shows set in Chicago.

The building occupies a site bound by Franklin Street, Jackson Boulevard, Wacker Drive, and Adams Street. Graham and Khan designed the building as nine square "tubes", clustered in a 3×3 matrix; seven of the tubes set back at upper floors. The tower has 108 stories as counted by standard methods, though the building's owners count the main roof as 109 and the mechanical penthouse roof as 110. The facade is made of anodized aluminum and black glass. The base of the building contains a retail complex known as the Catalog. The lower half of the tower was originally occupied by retail company Sears, which had its headquarters there until 1994, while the upper stories were rented out.

The Oriental Pearl Tower is a futurist TV tower in Lujiazui, Shanghai. Built from 1991 to 1994, the tower was the tallest structure in China until the completion of nearby World Financial Center in 2007. Its status as Shanghai's first AAAAA tourist attraction, the tower's unique architecture, height, and fifteen observation decks have made it a cultural icon of the city.
Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).

The Shanghai World Financial Center (SWFC; Chinese: 上海环球金融中心; pinyin: Shànghǎi Huánqiú Jīnróng Zhōngxīn, Shanghainese: Zånhae Guejieu Cinyon Tsonsin) is a supertall skyscraper located in the Pudong district of Shanghai. It was designed by Kohn Pedersen Fox and developed by the Mori Building Company, with Leslie E. Robertson Associates as its structural engineer and China State Construction Engineering Corp and Shanghai Construction (Group) General Co. as its main contractor. It is a mixed-use skyscraper, consisting of offices, hotels, conference rooms, and a ground-floor shopping mall.

On 14 September 2007, the skyscraper was topped out at 492 meters (1,614.2 ft), making it the 2nd tallest building in the world on completion (the tallest at the time being Taipei 101), the tallest building in the world by roof height only, and the tallest in mainland China. The SWFC opened to the public on 28 August 2008, with its (since closed) observation deck opening on 30 August. The observation deck offered views from 474 m (1,555 ft) above ground level.

30 Hudson Yards (also known during construction as the North Tower) is a supertall commercial skyscraper on the West Side of Midtown Manhattan in New York City. Located near Hell's Kitchen, Chelsea, and the Penn Station area, the building is part of the Hudson Yards Redevelopment Project, a plan to redevelop the Metropolitan Transportation Authority's West Side Yard. It is the seventh-tallest building in New York City and the ninth-tallest in the United States as of May 2025.

The building has a triangular observation deck, known as The Edge, jutting out from the 100th floor, with a bar and event space on the 101st floor. This observation deck, at 1,100 feet (340 m), opened in March 2020 and is the second-highest outdoor observation deck containing optically transparent flooring in the world, after Skywalk in Madeira. The building was formerly the headquarters for WarnerMedia until the company was merged with Discovery, Inc. in 2022 to form Warner Bros. Discovery, which remains a tenant. WBD subsidiary Home Box Office, Inc. is based at 30 Hudson Yards. The building also serves as the headquarters for Kohlberg Kravis Roberts & Co., an American global investment company.