China's first tunnel across the Yellow River was drilled through on Friday in Jinan, capital of east China's Shandong Province, according to the China Railway Construction Corporation Limited (CRCC). With a total length of 4.76 km, the tunnel contains two levels. A two-way six-lane highway is on the upper level and the lower level is reserved for rail transit, flues and escape channels. The 15.76-meter-diameter tunnel is the country's widest shield tunnel for both rail and road transport. The tunnel is expected to finish construction and open to traffic in 2021, which will strengthen the connection between Jinan's new district and its main urban zone.