The anticipation surrounding the arrival of the 3I Atlas comet has sparked intense discussions and significant preparations in various sectors, particularly in the US where plans for an enormous underground city are underway. This monumental project is aimed at providing shelter for tens of millions of people, highlighting the scale and seriousness of anticipated impacts from the comet. Leaked information points to this being a 'super project' unlike any other, designed to withstand extreme conditions potentially caused by the comet’s arrival. Such a facility would require advanced engineering to ensure safety, sustainability, and long-term habitability underground. Beyond the sheer engineering challenges, the concept reflects a growing interest in disaster preparedness and futuristic urban planning. Underground cities offer protection not only from celestial threats like comets but also from natural disasters, climate change, and other global emergencies. Communities worldwide are increasingly exploring innovative solutions akin to this underground city concept, integrating technology and sustainable resources such as renewable energy, water recycling, and air purification systems. The 3I Atlas comet event, referenced in hashtags like #3iatlas and #atlascomet, emphasizes a planetary-scale phenomenon prompting governments and scientists to rethink traditional infrastructure and safety measures. While details remain limited, the creation of such an underground city showcases human resilience and creativity in facing cosmic challenges. Ongoing updates on this project will be vital for understanding how societies prepare for rare but impactful space events, emphasizing the importance of global cooperation and advanced scientific research.