225 million years ago, the whole area of Ha Nam, Nam Dinh, Thai Binh and Ninh Binh lied deep beneath the sea. In the late Jurat or the beginning of Bach Phan, a movement made up limestone area in Ha Nam , Nam Dinh and Ninh Binh today. Most of the rocks distributed along the right bank of the Day River, there are very few hills located on the left bank.
About 70 million years ago, the sea regime ended, replaced by the deposition process to form the ancient delta. The new alluvial and the formation of the delta area on the basis of creating lowlands being the youngest sediments in the Northern delta. Ha Nam is a land enriched by the alluvial of the Red River and Day River and received the land eroded down from high mountains. In addition to the mountains, Ha Nam is also surrounded by rivers. It's the Red River in the east, Day River in the west, Nhue River in the north, Ninh River in the south and other rivers flowing in the territory of the province. It's the natural conditions that create this land’s historical and cultural characteristics of a interference region or transitional zone of culture from the east to the west, from the north to the south and these characteristics have made up the characters of Ha Nam people during the long history of construction and defense of the nation.
According to archaeologists, the primitive people appeared in Ha Nam in less than one thousand years, in the early Neolithic period and pottery period in Hoa Binh culture and Bac Son culture. It may be due to the population explosion from the primitive metal era that the residents began to plant rice in the delta. They were regarded as pioneers to exploit the North Delta.
