On June 24, 2018, major bus changes occurred in Columbia Pike. The 16X was eliminated due to multiple routes running through Columbia Pike in Arlington. The elimination of the 16X was to improve frequencies, and to reduce bus bunching on Columbia Pike, as there was routes 16A, 16B, 16G, 16H, 16J, 16K, 16P, and 16Y, operating on Columbia Pike. The 16X, alongside routes 16B, 16J, and 16P, was replaced by route 16C. This means that the entire route returns to the Columbia Pike Line, although the 16C only operates to Federal Triangle during peak hours, and operates on full routes instead of shortened routes. The short trips was permanently discontinued due to low riderships, as the Washington Metro Blue Line serves as an alternative of the short 16X trips.
