The Longmen caves stretch for about 1 km so be prepared to walk

  The Longmen Caves are open to the public for the price of 120 RMB (~17$), and indeed the experience is worth it. The caves stretch for about 1 km so be prepared to walk. Excellent caves to visit include the Bingyang caves. These three caves were some of the earliest to be developed in the Grottoes, and were built by the Northern Wei Dynasty from 500 to 523 AD.Vietnam tour

  It was not until 626 that the third phase began, during the height of the Tang dynasty, when Chinese Buddhism had begun to flourish again. This was once again a period of intensive cutting of grottoes; it was the highpoint artistically of Longmen, especially during the reigns of Emperor Gaozang and Empress Wuzetian, who lived permanently at Luoyang. The group of giant statues in Fengxiansi Cave is most fully representative of this phase of Chinese art at Longmen; they are generally acknowledged to be artistic masterpieces of truly global significance.
  The final phase, from 755 to 1127, during the later Tang through to the Northern Song dynasty, saw a steep decline in the carving of grottoes at Longmen. This began with the capture of Luoyang in the mid-8th century during a rebellion, an event from which the area never recovered. It was the outbreak of warfare during the Jin and Yuan dynasties that brought grotto carving to an end.