Occupying a total of some 100 hectares, Hà Nội's Old Quarter boasts over 1,000 years of history. When King Lý Thái Tổ moved his capital from Hoa Lư to Thăng Long in 1010 the Old Quarter was the trading hub of the new capital, and it was here in the 13th century that 36 guilds were established, each occupying a different street - hence the original name '36 Streets'. Today there are around 50 streets in the Old Quarter, most of them named after the merchandise originally produced by their residents, eg Hàng Gai (silk), Hàng Quạt (fans), Hàng Giày (shoes), Hàng Bạc (silver), although comparatively few streets now specialise in any particular trade. The 'tube house' design which predominates in the Old Quarter originally evolved in response to a tax on the width of shop fronts; surviving examples of the original design are just 2 to 4 metres wide and two storeys tall, with a shop in the front portion, rooms containing manufacturing or assembly facilities in the middle and residential and dining quarters in the rear. Unfortunately the older houses so beloved of conservationists generally offer cramped and substandard living conditions to the numerous families that share them, and not surprisingly many were destroyed during the 1980s and early 1990s in the rush to build more suitable accommodation. Over the past few few years the Hà Nội People's Committee has been seeking to balance the needs of modernisation and development with measures to protect what remains of the Old Quarter's architectural heritage. Hà Nội People's Committee has entrusted responsibility for the preservation, conservation and development of the Old Quarter to the Hà Nội Old Quarter Management Board, which has restored two of the quarter's most noteworthy houses (see below). Efforts are currently focused on seeking recognition of Hà Nội's Old Quarter as a UNESCO World Heritage Site.