Typological index of alleyways: mapping the pattern of a forgotten urban form element

Alleys have been neglected in the definition of urban form even though they have existed since antiquity and have served a variety of purposes. This paper identifies alleys as a critical space, especially at the neighbourhood scale. Neighbourhood samples belonging to different growth phases in Abu Dhabi and Dubai are taken as case studies to document the changing morphologies of alleys. Morphological mapping identified ten typologies of alleys. Findings indicate that sometimes alleys are equivalent to streets in terms of occupied land, pattern, density, and length, and in rare occasions, their physical attributes even surpass those of neighbourhood streets.