Light rail trains will likely be spotted in downtown Denver again starting on Monday, but regular service to downtown stations won’t begin until late September.

RTD announced Monday it will start running trains in advance of the official start to help new operators get familiar with the system, according to a news release.

The revenue service will begin on Sept. 29, marking completion of the first phase of RTD’s Downtown Rail Reconstruction project, which involves reconstruction to the rail track and infrastructure at several downtown intersections, according to the regional transit agency.

During the training, light rail trains will be marked as “not in service,” and RTD encouraged people traveling near the rail routes to be cautious through intersections. Operating hours are from 7 a.m. to 10 p.m. daily.

People should expect to see trains traveling “at normal speeds” through the downtown area “at all times and in any direction,” the release said.

The D and H lines will still be rerouted through Union Station and the L line will continue to be suspended until Sept. 29, as RTD completes its safety testing and trainings.

The transit authority will continue rail reconstruction work in 2025, with a final timeline still under development, the release said.

The reconstruction project focuses on investing in the agency’s 30-year-old rail infrastructure, which was put into service on Oct. 7, 1994.

“The multi-phased project will improve safety and mobility along the 30-year-old alignment,” the transit authority said.

More information about current RTD’s services is available online.