首都西北再添交通动脉，19号线二期北延及北延支线全面开工

Group 1 - The core point of the article is the successful commencement of the construction mobilization meeting for the second phase of Beijing's Metro Line 19, which includes the northern extension and its branch line [1] - The construction mobilization event took place on February 24, marking the first working day after the Spring Festival holiday [1] - The new Longze Station is a significant part of the Metro Line 19 phase two project, indicating progress in Beijing's urban transit infrastructure [1]