Observation tower in the context of Kotka

A tower is a tall structure, taller than it is wide, often by a significant factor. Towers are distinguished from masts by their lack of guy-wires and are therefore, along with tall buildings, self-supporting structures.

Towers are specifically distinguished from buildings in that they are built not to be habitable but to serve other functions using the height of the tower. For example, the height of a clock tower improves the visibility of the clock, and the height of a tower in a fortified building such as a castle increases the visibility of the surroundings for defensive purposes. Towers may also be built for observation, leisure, or telecommunication purposes. A tower can stand alone or be supported by adjacent buildings, or it may be a feature on top of a larger structure or building.

Tokyo Tower (東京タワー, Tōkyō Tawā; pronounced [toːkʲoː taꜜɰᵝaː] ), a.k.a. Japan Radio Tower (日本電波塔, Nippon denpatō) is a communications and observation tower in the district of Shiba-koen in Minato, Tokyo, Japan, completed in 1958. At 332.9 m (1,092 ft), it was the tallest tower in Japan until the construction of Tokyo Skytree in 2012. It is a lattice tower inspired by the Eiffel Tower, and is painted white and international orange to comply with air safety regulations.

The tower's main sources of income are tourism and antenna leasing. FootTown, a four-story building directly under the tower, houses museums, restaurants, and shops. Departing from there, guests can visit two observation decks. The two-story Main Deck (formerly known as the Main Observatory) is at 150 m (490 ft), while the smaller Top Deck (formerly known as the "Special Observatory") reaches a height of 249.6 m (819 ft). The names were changed following renovation of the top deck in 2018. The tower is repainted every five years, taking a year to complete the process.

The ArcelorMittal Orbit (often referred to as the Orbit Tower or its original name, Orbit) is a 114.5-metre (376-foot) sculpture and observation tower in Queen Elizabeth Olympic Park in Stratford, London. It is Britain's largest piece of public art, and is intended to be a permanent lasting legacy of London's hosting of the 2012 Summer Olympic and Paralympic Games, assisting in the post-Olympics regeneration of the Stratford area. Sited between London Stadium (formerly called the Olympic Stadium) and the Aquatics Centre, it allows visitors to view the whole Olympic Park from two observation platforms.

Orbit was designed by Turner Prize–winning artist Anish Kapoor and Cecil Balmond of Arup Group, an engineering firm. Announced on 31 March 2010, it was expected to be completed by December 2011. The project came about after Mayor of London Boris Johnson and Olympics Minister Tessa Jowell decided in 2008 that the Olympic Park needed "something extra". Designers were asked for ideas for an "Olympic tower" at least 100 metres (330 ft) high: Orbit was the unanimous choice from proposals considered by a nine-person advisory panel. Kapoor and Balmond believed that Orbit represented a radical advance in the architectural field of combining sculpture and structural engineering, and that it combined both stability and instability in a work that visitors can engage with and experience via an incorporated spiral walkway. It has been both praised and criticised for its bold design, and has especially received criticism as a vanity project of questionable lasting use or merit as a public art project.

A lattice tower, or truss tower, is a freestanding vertical framework tower. This construction is widely used in transmission towers carrying high-voltage electric power lines, in radio masts and towers (both self-radiating towers and those that support aerials) and in observation towers. Its advantage is good shear strength at a much lower weight than a tower of solid construction would have as well as lower wind resistance.

In structural engineering, the term lattice tower is used for a freestanding structure, while a lattice mast is a guyed mast supported by guy lines. Lattices of triangular (three-sided) cross-section are most common, particularly in North America. Square (four-sided) lattices are also widely used and are most common in Eurasia. A lattice towers is often designed as either a space frame or a hyperboloid structure.

An observation deck, observation platform, or viewing platform is an elevated sightseeing platform usually situated upon a tall architectural structure, such as a skyscraper or observation tower. Observation decks are sometimes enclosed from weather, and a few may include coin-operated telescopes for viewing distant features.

Reunion Tower is a 561 ft (171 m) observation tower in Dallas, and one of the city's most recognizable landmarks. The tower is located at 300 Reunion Boulevard in the Reunion district of downtown Dallas, which is named after the mid-nineteenth century commune La Reunion. A free-standing structure until the construction of an addition to the Hyatt Regency Dallas and surrounding complex in 1998, the tower is the city's 15th tallest occupiable structure. It was designed by architectural firm Welton Becket & Associates.