Cimolai Technology has contributed to the creation of the highest open-air building ascent called City Climb in New York

Proud of having contributed to the creation of the highest open-air building ascent called City Climb at Edge in New York


A unique project in the world has been brought to life, the highest open-air building ascent on the outside of a skyscraper at more than 1,200 feet above the ground.

We were in charge for the whole scope, from designing to constructing a 150m long path on top of the 30th Hudson Yards, where New York’s observation deck called Edge is located. The path is all manufactured in duplex stainless steel and is the result of a sequence of rail segments, placed side by side, with straight, inclined and curved sections along the way.


Cimolai Technology_City Climb_City Climb_The Stair_courtesy of Edge


The Project

Our ability stood in having put together this sequence of rails to create a special and unique path. We built and designed the custom rails and the related support brackets in an extremely precise manner, so that they would fit every single point on the building’s structure.

In addition, we designed and created a custom safety trolley, made with a special high resistance aluminium mainly used for aerospace applications, with very tight tolerances, in order to meet the highest safety and resistance requirements of the American Amusement Ride Standards.

The uniqueness, compared to other existing solutions on the market, is that all the attraction and the safety system developed prevent any kind of potential risk situation ensuring the user’s complete safety during the whole experience.

One of the innovative solutions of the trolley’s design is the anti-falling system, to prevent backward falls along the 161-Steps of the Stair. This anti-falling system is composed by a gear, in the fixed part, and a restraint system, a pawl, inside the trolley.



Moreover, the trolley is characterized by a very low weight (less than 2 kg) compared to the loads it can withstand. We were indeed able to satisfactorily carry out all the operative and strength tests on factory (FAT tests) including the application of a load up to 5000 kg (about 11,000 lbs).


Safety trolleys_cimolai technology

One year elapsed from the first contact with our Client Related to the commissioning on-site (SAT tests), and the project was completed.

We took care of the entire process of the project, including design, manufacturing and assembly of all the trolleys, rails and the brackets.


Enrico Onofri, Project Manager at Cimolai Technology, says: “The great challenges were having to comply with very tight tolerances while manufacturing all the rail elements to meet the as-built conditions of the existing building without field adjustments and the need to use a lightweight material for the trolleys, structural aluminium, that met the very high requirements of the American Amusement Ride Standards.”




Some technical data

Length of the path: about 150 m (about 500 ft)

Height reached at the Apex: 387 m (1,271 ft)

Rails in duplex stainless steel, designed to withstand concentrated loads up to 1800 kg (about 4,000 lbs)

Trolleys: manufactured with a final weight less than 2 kg/each (4 lbs) have been successfully tested to withstand to concentrated loads up to 5000 kg (about 11,000 lbs), more than the double minimum load required by the Standards.