Denver International Airport will shut down its concourse trains on Tuesday nights over the next three weeks in preparation for the arrival of 26 new trains later this year.

The closures will occur from 9:15 p.m. to 3 a.m. on Feb. 13 and 14, 20 and 21 and 27 and 28, and will affect passengers and employees getting to and from concourses B and C, according to a Thursday release. Travelers flying out of the concourses on these dates will have to pass through the 24-hour bridge security checkpoint starting at 8 p.m. and should plan on getting to the airport an extra half hour in advance.

While the trains are shut down, airport employees will be operating buses to transfer travelers between the concourses, the release said.

“DEN Operations is working hard to minimize the impact to passengers and employees, said Senior Vice President of Airport Operations Sarah Marquez in the release. “That is why we will have buses operating between the terminal and concourses, we’re working with airlines to communicate with traveling passengers in advance of their flights, we’re maximizing gate space on concourse A and it’s why the tests will be conducted overnight.”

The shutdowns are taking place to allow airport operations to test the trains’ electrical power distribution and infrastructure systems in preparation for 26 new trains arriving later this year, the release said.

“This effort will help ensure the resiliency of our automated people mover, the train, by evaluating the condition of aging electrical infrastructure while also providing critical information required for current operations and future expansion as we work toward 100 million annual passengers,” said Airport CEO Phil Washington.

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