Lookout towers are often more dramatic pieces of architecture than tall buildings because they only have a single floor -- the top one. This means that they can be very skeletal and the design is all about a dramatic staircase.
Here are some of our favourite examples, accidental architectural gems, like mini Eiffel Towers used for watching everything from forest fires to smugglers.
Situated on a site 18m above sea, with spectacular views of the sea and the city of Helsinki, the tower is a delicately transparent landmark of Korkeasaari Island.
Established in 1889 Helsinki's Korkeasaari Zoo, located on Korkeasaari Island, has animals from Finland and around the world housed in large natural enclosures.
Completed in 2000 the Killesberg tower is a 40m high observation tower, a cable-stayed construction designed by Jörg Schlaich.
An interesting variation on a fire watch tower.
This has since been replaced by a wooden structure. I like the odd shape of the platform and the fact that the spiral stair winds itself alongside the core, completely independently.
Although it is much shorter than the Eiffel Tower at around 60m, it stands on the Petrin hill, so the top is actually higher. It was built in 1891 and was used as an observation tower as well as a transmission tower.
In 1928 the Conservation Department's Division of State Parks erected a standard 18m Aermotor LS40 tower on Mt Tuscarora on the southwest side of Quaker Run. When jurisdiction over several State Parks towers was transferred to Forest Fire Control in 1931, Mt Tuscarora was not one of them. The Park retained jurisdiction and staffed the tower only in times of high fire danger.
Wind turbine with observation deck in Westerholt, Germany
Built on the Czech/German border. This lookout tower was built in the '70s to wiretap German radio signals.