how are the tombs numbered?
KV numbers were painted over the entrances to the 21 tombs that lay open in the East Valley at that time, as well as four tombs in the West Valley that he dubbed WV1 through WV4.
Valley of the Kings
Wilkinson painted KV numbers over the entrances to the 21 tombs that lay open in the East Valley at that time, as well as four tombs in the West Valley that he dubbed WV1 through WV4. 
how many pyramids are there in the valley of the kings It is known to contain 64 tombs and chambers (ranging in size from KV54, a simple pit, to KV5, a complex tomb with over 120 chambers) where is it located? Egypt who was the the first to explore the valley? Jules Baillet
wiki:12620138
Valley of the Kings [SEP] Tomb numbering
The modern abbreviation "KV" stands for "Kings' Valley". In 1827, Wilkinson painted KV numbers over the entrances to the 21 tombs that lay open in the East Valley at that time, as well as four tombs in the West Valley that he dubbed WV1 through WV4. The tombs in the West Valley were later incorporated into the East Valley numbering system as WV22 through WV25, and tombs that have been opened since Wilkinson's time have been added to the list. The numbers range from KV1 (Rameses VII) to KV64 (discovered in 2012). Since the early 19th century AD, antiquarians and archaeologists have cleared and recorded tombs, with a total of 61 sepulchers being known by the start of the 20th century.