Archways are built as memorial statues to commemorate special events, usually assigned by the government through out the history. There used to be more than 100 memorial archways on this street. Due to the ages of the structure, fallen stones endangered passersby, hence all were taken down, only about 30 are rebuilt in new structures today.
They are lit up at night. I am not very fond of this modernization of the tradition. Some times you just can't mix the new and the old.