The Yingxian Wooden Pagoda in Shanxi is the oldest and tallest existing pavilion-style structure built entirely of timber. Together with the Leaning Tower of Pisa in Italy and the Eiffel Tower in Paris, it is considered one of the Three Wonder of Towers in the world. Since the 1970s, wind and rain erosion have caused the pagoda serious problems, including slanting and structural compression. The country is now conducting extensive renovation work, looking to preserve this ancient building of great historical, religious and artistic value.