A view from the word’s tallest tower

The CN Tower located in Toronto, Canada, is an amusing freestanding structure. This is a recognizable symbol of the city. At a height of 553 meters, it is the tallest all over the world, what causes that every year a lot of visitors are attracted to be on the top, so do I ;-).

This photo has been taken by Barbara Ropa (with some difficulties ;-)).

According to some statistic data each year approximately 2 million people visit the CN Tower and everyone is carefully checked by security service.

To get at the top of tower without doubt you should choice a sunny day to enjoy perfect view, additionally it is better to go there on weekday (to avoid crowds of people). Moreover be prepare to spend quite a big amount of many (tickets are really very expensive; luckily I had a special offer ;-)). Oh... and one thing more, my personal advice: to enjoy being there it is necessary to have lovely company and together admire a mysteriously lighting of Toronto and the Lake Ontario when dust is coming...

This photo has been taken from Sky Pod by Barbara Ropa.

Ok and now some facts. The CN Tower was completed in 1976 (the construction has began on February 1973). And the whole name is: Canada's National Tower. This is an important telecommunications hub, actually this was a major purpose to build it, when the construction was started nobody was thinking about tourist value. Moreover nobody was considering beating a record for the tallest tower, it happened just because of the technical reasons. Well, the tower is located near Financial District in Toronto, which is dotted with skyscrapers. So to have good telecommunications signals the architects were obligated to design very tall tower.

This photo has been taken by Barbara Ropa.

Nowadays, due to tourist business, guests can find other attractions. At a height of 342 m is located Glass Floor and Outdoor Observation Deck. What surprised me, well Outdoor Observation Deck was more exciting then a dick indoor Glass Flour ;-). Maybe because of factors like: sound of a city and a puff of a wind on my face what I could feel being outside .

This photo has been taken from Sky Pod by Barbara Ropa.

At 346 m is Horizons Cafe and the Indoor Observation Deck. At 351 m, is located 360 restaurant, why named 360, simply, the floor in the 360 Restaurant rotates once every 72 minutes allowing to take in the breath-taking view. And what you can not miss, is Sky Pod which is the World's Highest Public Observation Deck located at 447 m.

Construction data:

The tower consists of 40,522 cubic meters of concrete, 129 km of post-tensioned steel, and 5,080 metric tons of reinforcing steel. The tower is estimated to weigh 132,080 metric tons.

The elevators travel at a speed of 6 m per second, reaching the Sky Pod in just under one minute (58 seconds). I really could feel this speed ;-(

For all of its 553 meters, the shaft penetrates only 6 meters into a total 15 meter foundation.

The CN Tower is a member of the World Federation of Great Towers.

Construction of the CN Tower cost approximately CAD$63 million.

Crossing the bridges in Istanbul, Turkey

Istanbul is lovely city, very multicultural which embraces two continents. Probably, my first thought on Istanbul will be: incredible big diversity of almost everything on the one hand, and on the other great unity which I found out in this city. From my point of view those two incredible suspension bridges in Istanbul are more then just a way to cross the Bosphorus. There are also symbols of connection between cultures, religion, trade etc. with one arm reaching out to Asia and the other to Europe. So let me now focus on them.

One is called Bosphorus Bridge I, built in: 1970-1974.

What was special? ... Well it was the 4th longest suspension bridge in the world when was completed, and the longest outside the United States of America.

The Bosphorus Bridge was finished on 30th October 1973, one day after the 50th anniversary of the founding of the Republic of Turkey.

The core function is highway (no pedestrians are allowed to use the bridge today – maybe due to many suicides in previous years).

The designer:

- William Brown (also a designer of suspension: Messina Straits Bridge in Italy, which should be finished in 2012, he worked for Freeman Fox & Partners, renamed as Acer Consultants and currently renamed: Hyder Consulting Ltd.UK, he died in March 2005);

- Gilbert Roberts (born in London in 1899, deceased in 1978. He worked for Freeman Fox & Partners as well. He was a designer of: cantilever truss bridge Auckland Harbour Bridge – built in 1959 in New Zealand; suspension Forth Road Bridge – built in 1964 near Edinburgh in UK, suspension Humber Bridge – built in 1981 in UK. He was also an Engineer of arch bridge: Sydney Harbour Bridge – built in 1932 in Australia).

Firms involved with this structure:

- Structural Engineering: Freeman Fox & Partners (UK)

- Construction: Enka Construction & Industry Co. Inc. (TUR)

- Co-constructor: Cleveland Bridge & Engineering Co. Ltd. (UK, this company was one for instance involved in the construction of Millennium Bridge in London) and Hochtief AG (GER)

Some of the technical information:

It is suspension bridge with a gravity-anchored, inclined hangers and steel pylons. The aerodynamic deck is hanging on zigzag steel cables as distinct from the Fatih Sultan Mehmet Bridge (second suspension bridge in Istanbul) where steel cables are parallel to each other. Construction material used to build cables and pylons: steel.

Dimensions: It is 1,560 m long with a deck width of 39 m. (Main span: 1074m; Span lengths: 40 m - 3 x 45 m - 56 m - 1 074 m - 4 x 63.75 m what makes 1560m long) The distance between the towers (main span) is 1,074 m (World rank: 13th) and the clearance of the bridge from sea level is 64 m.

The cost of the bridge amounted to 200 million USD.

This picture of Bosphorus Bridge has been taken by Barbara Ropa from the ferry.

The second one suspension bridge over Bosphorus is Fatih Sultan Mehamt Bridge.

The bridge is named after Ottoman Sultan Mehamet the Conqueror, who captured Istanbul in 1453 and ended Byzantine Empire. This bridge was built in1986 – 1988 and it was the 6th longest suspension bridge in the world when completed in 1988. The core function is highway. (No pedestrians are allowed to use the bridge).

Some technical information:

It is a gravity-anchored suspension bridge with steel portal frames. The aerodynamic deck is hanging on double vertical steel cables. It is 1,510 m long with a deck width of 39 m. The main span is 1,090 m long. The clearance of the bridge from sea level is 64 m.

Firms involved with this structure:

- Designer: Acer Consultants (UK – formerly named Freeman Fox & Partners); Bosphorus Technical Consulting Corporation (TUR)

- Co-contractor: An international consortium of three Japanese companies (a. Ishikawajima-Harima Heavy Industries – mainly activities are bridges, at this moment engaged in construction of railroad & road bridge Messina Stairs Bridge between Sicily and Italy ; b. Mitsubishi Heavy Industries Ltd. ; Nippon Kokan), one Italian (Impregilo S.p.A. - for instance involved in Mont Blanc Tunnel rehabilitation) and one Turkish company carried out the construction(STFA Group)

The cost of the bridge amounted to USD 130 million.

This picture of Fatih Sultan Mehamt Bridge has been taken by Barbara Ropa from ITU Maslak Campus.

Plans for the future investments in Istanbul: Project Marmaray.

The purpose of this project is to link the European and Anatolian halves of Istanbul by an undersea rail tunnel across the Bosphorus strait. The name Marmaray comes from combining the name of the Sea of Marmara, with ray, the Turkish word for rail. Construction of the Marmaray project started in May 2004 and completion is expected to occur in 2009. Without doubts, a biggest challenge for this project from my point of view can be difficulties with design and construction in the earthquake zone.