Learn more about Observation tower
An observation tower is a structure used to view events from a long distance and to create a full 360 degree range of vision. They are usually at least 20 meters tall and made from stone, iron, and wood. Many modern towers are also used as TV towers, restaurants, or churches. The towers first appeared in Germany at the end of the 18th century, and their numbers steadily increased, especially after the invention of the elevator. There are many notable observation towers in the world today.
 Construction and usage
Observation towers are an easily visible sight on the countryside, as they must rise over trees and other obstacles to ensure clear vision. Older control rooms have often been likened to medieval chambers. The heavy use of stone, iron, and wood in their construction helps to create this illusion. Modern towers frequently have viewing platforms or terraces with restaurants or on the roof of mountain stations of an aerial ropeway. Frequently observation towers are used also as location of radio services within the UHF/VHF range (FM sound broadcasting, TV, public rural broadcasting service, and portable radio service). In some cases this usage of the tower is at least as important as its use as an observation tower. Such towers are usually called TV towers or telecommunication towers. Many towers are also equipped with a tower restaurant and allow visitors access via elevators. Also common is the usage of water towers as observation towers. As in the case of TV towers the visitor will usually reach the observation platform by elevator, which is usually at a lower height above ground The typical height of the observation platform of water towers is 20 meters up to 50 meters, while the typical height of the platform of TV towers is from 80 meters up to 200 meters. Finally, some church towers may have observation platforms, albeit often without an elevator. Many other buildings may have towers which allow for observation.
In Germany, observation towers first appeared on the countryside at the end of the 18th century. These early towers were often built by wealthy aristocrats. It wasn't until the mid-19th century that citizens took control of the construction of such towers. In Austria and Switzerland many observation towers were established by alpine and tourist associations, and continue to be cared for by them. In the Waldigen Mountains, many citizen committees were active. Because of the long reign of emperor Franz Joseph, many observation platforms carry the name "anniversary observation platform". The invention of the elevator in the late 19th century made taller observation platforms possible. Most notably, the Eiffelturm and the Blackpool Tower were built in this era. Radio towers developed as combined sending and observation tower between 1924 and 1926 in the city of Berlin. After the second world war, a great need for tall observation towers arose, due to their dual usage as television and radio transmitters. In large cities, the desire existed to provide these towers with a tower restaurant and a viewing platform, in order to make the building of towers more economical via admission fees and increased notability. Several water towers were also built with this in mind, but many have not survived to the modern day.
 Special observation towers
Radio Tower Berlin is a radio tower in Berlin, standing 150 meters tall. It was built by Straumer, and has a steel lattice construction. It was inaugurated on September 3, 1926, to much delight by citizens, as it was a technological achievement at that time. The first world-wide FM radio programs were broadcast from this tower. It also broadcast the first regular television program, the 1936 Olympics. The tower is the only radio tower which holds an insulator to have an observation deck.
Hennigen Turm is the world's only silo tower with an observation deck accessible to the public.
Windpark Holtriem is the only windmill with an observation deck accessible to the public.
Torre Jaume I is a support pillar of the aerial tramway in Barcelona. It is equipped with an observation deck.
Joachim Kleinmanns: Schau ins Land. Aussichtstürme. Marburg: Jonas-Verlag, 1999, 152 S. brosch., 20 EUR, ISBN 3-89445-252-8