Complex sentence: Modern Plovdiv covers an area of, less than 0.1% of Bulgaria's total area, and is the most densely populated city in the country with 3,769 inhabitants per km².
Split into simpler sentences: Modern Plovdiv covers an area of, which is less than 0.1% of Bulgaria's total area. This makes Plovdiv the most densely populated city in the country with 3,769 inhabitants per km².