How entrenched is the spatial structure of inequality in cities? Although recent discussions provide conflicting answers to this question, the absence of long-term, longitudinal neighborhood data curtails direct examination of the issue. Focusing on the city of Denver, we develop a new strategy for analyzing neighborhood dynamics from 1940 to the present day. Our analysis of these data reveals surprising persistence in the income rank of neighborhoods between 1940 and 2016, which appears to be driven by the enduring position of white, upper-income places at the top of the neighborhood hierarchy. When low-income neighborhoods do rise in income rank, we find that change tends to be spatially concentrated in specific areas of the city and accelerates during broader historical episodes of urban change. We conclude that neighborhood inequality in Denver has endured over long periods of time and through substantial shifts in the wider urban landscape. Key Words: gentrification, GIS, inequality, neighborhoods, spatial demography.