Urban Land Cover Dynamics in Pyongyang over 55 Years (1967–2022): Combining Declassified CORONA Colorization with GLC_FCS30D Multi-Epoch Analysis

Quantitative land cover records for geopolitically restricted regions remain extremely scarce, particularly for the pre-Landsat era. This study reconstructs long-term urban land cover dynamics in Pyongyang, Democratic People’s Republic of Korea (DPRK), over a 55-year span (1967–2022) by combining deep learning colorization of declassified CORONA KH-4 panchromatic imagery with the GLC_FCS30D global 30 m land cover dynamics dataset. The GLC_FCS30D nine-epoch time series (1985–2022) revealed that built-up area expanded from 65.0 km2 (36.0%) to a peak of 103.2 km2 (57.1%) in 2015, driven almost entirely by the conversion of agricultural land, before declining to 92.7 km2 (51.3%) by 2022. The 1967 colorization-based classification yielded a built-up proportion of 35.9%, closely approximating the 1985 baseline. Integration of these results identified three urbanization phases: post-reconstruction consolidation (1967–1985), sustained expansion at the expense of agricultural land (1985–2015), and stabilization coinciding with intensified international sanctions and pandemic-related isolation (2015–2022). The near-halving of agricultural land within the capital’s vicinity during chronic national food insecurity is consistent with a fundamental tension between showcase urban modernization and food production imperatives in state-planned economies. As perhaps the last continuously state-planned socialist city, Pyongyang’s trajectory offers a rare empirical counterpoint to market-driven urbanization processes.