Not only Agra but the whole region including Mathura and Vrindavan have a unique place in the cultural world of India. While Agra is known for its historical monuments, Mathura and Vrindavan are basically known as the major pilgrimage centers for Hindus for their long association with Lord Krishna. Both these sister cities have a number of significant and beautiful temples. The other place that is worth visiting near Agra is the Keladeo Bird Sanctuary of Bharatpur where a number of birds find their refuge and is ornithologist's delight.