DIA train mishap

The security lines at Denver International Airport after a train malfunction caused backups, delaying some passengers more than two hours getting to their gates.

As the dog days of summer are coming to a close, Denver International Airport is preparing for the busiest weekend of travel since the start of the COVID-19 pandemic. 

More than 1.1 million passengers are projected to walk through the security lines at the airport beginning Thursday.

Thursday and Friday are expected to be the busiest of the holiday weekend as more than 400,000 passengers will take off from Denver each day, said Alex Renteria, a spokeswoman for the airport.

"It's exciting to see more passengers traveling through the airport, because that means we're getting closer to what our new normal is," Renteria said. "We are still a ways away from our normal numbers from 2019; however, it's clear that people are excited to spend this long weekend, whether being with family or friends away from home."

Travel numbers are 109% higher than last year and only 5% lower than 2019, according to the airport. 

As the airport prepares for the influx of travelers this weekend, free bag drop-off service resumed on Wednesday. The service allows travelers to bring their boarding passes and check bags before going through security or reaching the terminal. 

The service is offered for domestic flights with American, Delta, Spirit and United airlines. Southwest passengers can start utilizing the service on Sunday, according to the airport. 

Despite more people becoming vaccinated officials want to remind travelers that masks are still required inside the airport and on all flights.