Barcelona’s La Sagrada Familia is a towering Roman Catholic cathedral that has been under construction for as long as Canada has existed. It’s a symbol of a city with a focus on the long term.
But, unbeknownst to the three million-plus tourists flocking to the Gaudí shrine every year, a vast network of cables and sensors snakes underneath, part of a 42-kilometre tunnel system that makes its way through the city, melding the Internet of Things with the city’s medieval roots.
The tunnels are comprised of fibre-optic lines, traffic signal cables, heating and cooling networks and gas and phreatic water canals. Those water canals are linked with rain sensors that know when to water the city’s parks and gardens; public fountains have timers to monitor and control the flow of water, all in an effort to cut down the city’s water usage.
It’s part of the burgeoning smart-city movement that has captured the attention of local and regional governments—along with tech firms angling for a piece of the action—across the globe.