Why is Nanchong called "the birthplace of Spring Festival culture"?

Langzhong City, Nanchong is of specimen significance in inheriting and protecting the cultural resources of the Spring Festival throughout the country. Where the Spring Festival comes from, we should start with the 24 solar terms. In 65438 BC+065438 BC+00 BC, Luo, an archaeologist in Langzhong, determined the summer solstice and winter solstice according to the length of day and night in a year, and also established 24 solar terms such as beginning of spring and rain. Since then, the Spring Festival has appeared in history as a fixed festival, and has been awarded the hometown of Spring Festival culture by the relevant state departments.