For the first time since it opened in 1978, Edmonton’s LRT will shut down for the day Sunday.

The city will be testing out a new signal system which will allow two trains to run on the same line.

In the meantime, Edmonton Transit System buses will run between each LRT station every seven to eight minutes to accommodate for the shut down.

The new Metro LRT line was expected to open this spring, but was delayed because the new signalling system was not ready. Although all of the infrastructure was completed on time and under budget, the line will not be ready until the end of 2014.

The city says there may be additional delays in the future, depending on how much progress is made Sunday.