The Gordie Howe International Bridge is easily one of the most ambitious infrastructure projects unfolding anywhere on the continent, and this record-breaker of a U.S.-Canada link is now reaching a dramatic stage of construction as its two ends begin to extend across the Detroit River.

Once completed, it will stand as the longest cable-stayed bridge in North America, relieve congested border crossings between Detroit and Windsor, and close a missing international trucking link by creating a direct connection between Highway 401 in Ontario and I-75 in Michigan.

Aerial photography shows off the immense scale of the project, which will shatter the record for the continent's longest cable-stayed bridge, almost doubling the existing record held by B.C.'s Port Mann Bridge and its 470-metre span over the Fraser River.

Measuring up against a more familiar landmark, the Gordie Howe Bridge's main span over the Detroit River will be approximately 66 per cent the length of the iconic Golden Gate Bridge in San Francisco, which stretches roughly 1,280 metres across San Francisco Bay.

Construction has been active on both sides of the U.S.-Canada border since October 2018, staffed by 3,900 workers operating in tandem on opposite sides of the river.

Crews on both the U.S. and Canadian sides of the bridge are currently making swift progress on some of the project's most important elements, and work has heated up over the past few months.

The main support towers are nearing their final heights of 220 metres/722 feet, just two metres shy of Detroit's tallest building, the Detroit Marriott at the Renaissance Center. The towers will be almost double the height of Windsor's tallest building, the 111-metre Caesars Windsor Augustus Tower.

Even just the prep work to construct foundations for these towers was a massive undertaking. Each tower is supported by a pair of pylon legs anchored to footings, hiding extensive engineering work below.

These footings were secured atop six shafts drilled 36 metres/118 feet into the bedrock — the equivalent of a 10-storey building — which were filled with approximately 262,000 litres/69,000 gallons of concrete and 1,600 metres/5,250 feet of post-tensioning cables.

As the towers wrap up, the bridge deck now begins to extend over the river from both ends. This six-lane road deck may look precarious but it is firmly fixed to the support towers via the growing network of stay cables.

Workers will eventually install a total of 216 stay cables to support the main bridge span, in a process that takes between two and five days per cable.

Cables are fed through welded-together sections of white, weather-resistant, high-density polyethylene plastic pipes and attached to the support towers in a highly technical and precise process.

Construction activity is also progressing smoothly for the bridge's approach spans and the new ports of entry to process the impending flood of cross-border traffic looking to bypass Windsor and Detroit.

Most recently, the Canadian Border Service Agency began a hiring blitz to staff the bridge, with the 18-month employment drive seeking to bring on 200 new border services officers to work at the new Port of Entry currently under construction on the Canadian side of the border.

The Gordie Howe International Bridge is set to open in 2025, taking pressure off the congested Detroit-Windsor Tunnel and Ambassador Bridge upriver.