What is associated with: construction of the world famous palazzo vecchio began in 1299 in this italian city?

Based on the clue 'construction continued on this fortification up to...', what is the answer? Based on the clue 'construction of the aswan high dam which holds bac...', what is the answer? What is associated with: construction of the empire state building began in 1930 on the site of this hyphenated hotel t… What is associated with: construction of the potala palace began in this mountainous asian capital in 1645? What is associated with: construction of this asian capital city near rawalpindi began in 1961? What is associated with: construction of this dc cathedral began in 1907 was still going on in the 1990s? What is associated with: construction of this famous british cathedral on the river avon began in 1220? What is associated with: construction of this pakistani capital began in 1961?