Lahijan in context: Street-network sprawl trends

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Lahijan plotted against Gilan and Iran. The SNDi of new construction in Lahijan was at its lowest in 1976-1990, compared to Gilan which rose steadily and Iran which rose steadily. Most recently, Lahijan's incremental SNDi rose from 3.02 to 3.58 between 1991-2005 and 2006-2020. In terms of the aggregate network, Lahijan ranked 1st out of 4 cities in Gilan and 48th out of 169 in Iran as of 2020.

Rankings go from most connected to most disconnected — rank 1 is the most connected.

What about similarly populated cities?

• Cary, United States
• La Louvière, Belgium
• Gʻuzor, Uzbekistan
• Panlongcheng Economic Development Zone, China
• Luodong, Taiwan
• Sainagar, India

In new street additions, Lahijan built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns, while Cary built increasingly disconnected streets from 1975 through 1976-1990, then improved and Panlongcheng Economic Development Zone fluctuated in its street-construction patterns. For the full network, Lahijan became more connected from 1975 through 1976-1990, then grew more sprawly from 1976-1990 onwards, while Cary grew more disconnected from 1975 through 1991-2005, then improved and Panlongcheng Economic Development Zone fluctuated in connectivity.