Northern Vietnam gets fewer visitors than Ho Chi Minh City and the coastal cities in the south, but it's full of culture. Historically, and to this day, it has been significantly poorer than the southern part of the country.
Hanoi, the capital of Vietnam, and also its second largest city, is a fascinating blend of East and West, with Chinese influence from centuries of dominance, and French je ne sais quoi from its colonial past.
Cao Bằng is the capital of Cao Bằng province in northern Vietnam. While unremarkable in and of itself, Cao Bằng is an easy-going gateway to the surrounding lakes, minority villages, karst peaks, caves, and the Ban Gioc Waterfall on the Chinese border.
Co To Island is in Quang Ninh province in Northern Vietnam. Co To island is an archipelago located in the Gulf of Tonkin, including a large Co To Island, a small Co islands, the island of Thanh Lam, Tran and countless islands and small island.