The 29.2-kilometer Hangzhou Bay Cross-Sea Railway Bridge, set to become the world’s longest cross-sea railway bridge, reached a major milestone on October 20 with the successful closure of its Northern Navigation Channel Bridge. Designed for speeds of up to 350 km/h, it will strengthen connectivity across China’s Yangtze River Delta. CGTN reporter Chen Yilin visits the construction site to see how engineers are tackling the challenge of building across Hangzhou Bay’s powerful tides.