Construction began in 1248 on which German city's Gothic cathedral near the Rhine, taking 632 years to finish?

Constantinople officially became which city in 1930? Four European armies met at Constantinople in 1097 to launch the first of which campaigns? Which Asian island nation fought a long civil war between its Tamil and Sinhalese communities that ended in 2009? Construction and maintenance costs of which New York waterway were paid for by tolls until 1882? Construction of the Empire State Building began in 1930 on the former site of which hotel, which moved to Park Avenue? Construction of the Potala Palace began in 1645 in which mountainous Asian city? Construction of the famous Palazzo Vecchio began in 1299 in which Italian city? Construction of which Asian capital city, near Rawalpindi, began in 1961?