When travelling by train in and out of Basel station, there is one building that stands out above the rest – the city’s central railway signal box.
Affectionately known as the "Copper Tower", the striking building is the work of local star architects Jacques Herzog and Pierre de Meuron.
Built in 1998-1999, the concrete structure is wrapped with copper strips that are twisted at certain places to allow in daylight.
The copper coiling also acts as a Faraday cage protecting the sensitive electronic equipment of the signal box from lightning strikes.
"It is something special. If I tell someone that I work at Münchensteinerstrasse 115 in Basel, they might not have a clue, but when I say I work in the copper tower, the main rail operations centre, that’s something most people know," one of the managers, Stefan Solèr, told swissinfo.
Such is the sophistication of the electronics inside that it needed two years to install it after construction of the building was finished in 1999.
While much has been written about the architecture and the exterior of the building, the inside has been somewhat ignored, with many wondering what actually happens behind all the copper and concrete.
"We have about 60 people who work around the clock in shifts. They are mostly operations controllers. They are the people who watch over what the trains are doing and control them," explained Solèr.
The operations centre - this describes the building more accurately than signal box - has a control room on the top floor that is the brains of train movements throughout northwest Switzerland.
In November 2004 alone it was watching over more than 700 passenger trains, 100 goods trains, 347 sets of points, almost 900 signals, 70 sections of track and five level crossings.
The train controllers seem to have their eyes everywhere and this is essential.
"They’re surrounded by between eight and 12 screens on which are displayed particular areas. It can be Basel station itself or a stretch of line that includes a number of stations," Solèr said.
Solèr has been in the job for more than 30 years and understands that the bank of monitors looks daunting to an outsider.
"At first glance, it is perhaps confusing. But if I look at the workplace of someone at the stock exchange that has the same number of screens and I don’t understand a thing. Here I can understand what’s going on," Solèr said.
"From the north-west we cover [access to] more or less the whole of Switzerland. When something goes wrong here, it can quickly have consequences for the rest of the network," he added.
Signal boxes used to be places with plenty of windows so that people had a good view of what was happening outside. Modern technology has done away with that.
Daylight comes into the Basel offices mostly from one side, but too much can hamper smooth operations.
"In the control room, it’s almost too gloomy but it is an advantage for working with screens. A room with too much light would make it more difficult to read what’s on the monitors," explained Solèr.
Behind a bank of screens, controller Stephan Baumgartner made it all sound rather easy.
"Putting it simply, my job is to make sure the trains are on time and on the right track," he said.
"Most of it is controlled by computer, but as soon as a train is one or two minutes behind schedule, I have to do things manually."
"I can set the signals to red and green, switch the points and, for example, make train announcements," he added.
There is a catalogue of events that can throw a spanner in the works of smooth operations, including a technical fault in the centre itself, a train that breaks down and blocks the line, an electricity failure, and platform closures or changes.
"Basically there is a set of regulations for all situations," explained Solèr.
"When there is an unusual event, we all act according to the same set of what I like to call game rules and there are also checklists in these situations," he added
Solèr said that the one of the most exciting parts of a job in the control centre was that no two days were ever the same and there were always surprises.
"One single element can upset things. You can manage relatively well when there’s a problem with a signal or a set of points."
"But unfortunately, it sometimes happens that an entire control centre goes out of service for a while and then you have to improvise. It gets a bit hectic sometimes," he added.
One of the main priorities in the centre is punctuality - to ensure that trains run according to the timetable and that platforms are not blocked when they should be free. And that requires teamwork.
"Everyone has to work for the same goal. People who like to work on their own are really not in the right place here. Teamwork is very important," Solèr said.
swissinfo, Robert Brookes in Basel
Basel’s central operations centre opened in April 2001 at a total cost of SFr102 million ($85.17 million).
It replaced three old signal boxes and controls rail operations in northwest Switzerland.
Star architects Jacques Herzog and Pierre de Meuron also designed Signal Box 4 in Basel’s goods yard (1994), a building that has received a number of architectural accolades.
Herzog and de Meuron have won a string of awards for their architecture, including the 2001 Pritzker prize.
Their most dramatic work in size and scale is perhaps the conversion of a large power plant on the River Thames in London into the new Tate Gallery of Modern Art.
It was a widely hailed centrepiece of the city’s Millennium celebrations.