Core Viewpoint - The newly opened exhibition hall at the southeast corner station of Tianjin Metro Line 4 showcases the historical relics of the East City Wall of Tianjin Wei, allowing passengers to learn about the city's history during their travels [1] Summary by Sections - Discovery and Preservation - The relics were discovered during the construction of Tianjin Metro Line 4 in 2017, identified as remnants of the East City Wall from the Ming and Qing dynasties [1] - The site has been preserved in its original state and effectively utilized for display [1] - Exhibition Features - The exhibition hall features a 21-meter-long section of the city wall, providing a clear and layered view of the historical structure [1]