Greenwich, London
stonehenge
It is famous astronomical observatory built by a king.
River Thames
The Arecibo Observatory is in the United States of America. It is in the municipality of Arecibo which is in Puerto Rico. It is a very famous radio telescope.
The River Thames is the major river through London, cutting right through the middle of the city. There are many other rivers in London, such as the River Lee (or Lea) and the River Brent.
The river Thames (pronounced temz)
The Thames River that runs through London is probably the most famous.
Griffith
Greenwich
Which famous landmark are you asking about. There's more than one along the Thames.
Old Father Thames.
A few astronomical clocks exist in different parts of the world. If you are referring to the famous astronomical clock located in Prague, Czech Republic, it is found in Old Town City Hall and is still functioning.