For a short period at the end of the first millennium (A.D. 968-1009), Hoa Lu was the capital of Vietnam under the Dinh dynasty and the first part of the Le dynasty.
The area was chosen because the limestone formations surrounding the site -- the same ones that attract tourists by the thousands -- were a stalwart natural defense against the Chinese. The temples of Hoa Lu are worth a visit and part of most itineraries out of Ninh Binh.
The two temples, both dedicated to respective Le and Dinh kings, are ornate 17th-century re-creations on the site of some ancient ramparts and walls, but what makes the trip interesting is the beautiful scenery of the area, especially along the rural road connecting the site with nearby Tam Coc.
The whole valley is hemmed in with high limestone walls of karst much like the dynamic setting of Tam Coc. One temple honors Dinh Tien Hoang with an imposing statue. The other temple, farther from the road across a large field often used for large festivals, is dedicated to Le Dai Hanh, one of Dinh's generals and the first king of the Le dynasty, who grabbed power in A.D. 980 after Dinh was mysteriously assassinated.
Hoa Lu can easily be seen on a day trip from Hanoi. The temples are 113km (70 miles) south of Hanoi.