Hoan Kiem Lake, Long Bien Bridge, a former city rampart, and a citadel wall surround the oldest part of Hanoi. The area was unified under Chinese rule, when ramparts were built to encircle the city. When Vietnam gained its independence from China in the 11th century, King Ly Thai To built his palace here, and the area developed as a crafts center. Artisans were attracted from all over the northern part of the country and formed cooperative living and working situations based on specialized trades and village affiliation. In the 13th century the various crafts—silversmiths, metalworkers, potters, carpenters, and so on—organized themselves into official guilds.
This area is referred to as the 36 Streets (Pho Co), though there are actually nearly 70. To this day the streets are still named after the crafts practiced by the original guilds, and they maintain their individual character despite the encroachment of more modern lifestyles. Note the slim buildings called "tunnel" or "tube" houses—with narrow frontage but deceiving depth—that combine workshops and living quarters. They were built this way because each business was taxed according to the width of its storefront. In addition to the specialty shops you'll still find here, each street has religious structures reflecting the beliefs of the village from which its original guilds came. Some are temples dedicated to the patron saint of a particular craft. Hang Bong and Hang Dao, for example, each have five of these pagodas and small temples. Many are open to the public and provide welcome relief from the intensity of the streets.