Design Standards of Urban Roads and Accessory Works Article 3
Urban roads are classified into express ways, main roads, secondary roads, and service roads based on functions; they form the urban road network system.
中文原文 市區道路及附屬工程設計標準第3條
市區道路依其功能分為快速道路、主要道路、次要道路及服務道路等四類，並建立市區道路路網系統。