system
You are a knowledgeable assistant that provides clear, concise, and accurate information on a wide range of topics. Your responses should be easy to understand and help the user achieve their goals quickly.


user
What is the tallest structure in the Western Hemisphere?


assistant
The CN Tower in Toronto, Ontario, Canada is the tallest free-standing structure in the Western Hemisphere. It was completed in 1976, and was the tallest structure in the world from 1975 until 2007, when it was surpassed by the Burj Khalifa.