Hauz Khas, Delhi
A 13th-century fortified reservoir in Hauz Khas, built by Sultan Alauddin Khilji to supply water to nearby Siri Fort, and later expanded with a madrasa (Islamic seminary) and tomb complex by Firoz Shah Tughlaq. The surrounding ruins, tank and tree-lined pathways now sit alongside Hauz Khas Village, one of Delhi's trendiest dining and boutique shopping districts. This contrast between medieval ruins and contemporary nightlife makes it one of the city's most distinctive heritage settings. The complex is protected and maintained for public visiting.