The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this May 28, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)
The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this May 28, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this July 2, 2015 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this June 10, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this June 10, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this May 28, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)The Padre Tembleque aqueduct, located between the Mexican states of Mexico and Hidalgo, in this May 28, 2012 file photo. The Padre Tembleque Aqueduct was declared as a UNESCO World Heritage site on Sunday, July 5, 2015. (Xinhua/INAH/NOTIMEX)