The Valley of Temples is a location in Nepal that appears in Uncharted 2: Among Thieves. The present day city was built on top of the "hundreds of gilded spires" that Marco Polo described. This location is playable in eight chapters of Uncharted 2:
When Marco Polo first discovered the valley on his travels to find Shambhala, the valley was occupied only by the hundreds of temples. On Marco Polo's map, found by Nathan Drake in Borneo, he describes, in Latin, the sheer scale of his find and its place in the search for Shambhala.
"Between Greater India and the Province of Tibet lies a field of exquisitely finished Temples.
Hundreds of Gilded Spires stretching as far as the eye can see.
Of all these many Temples only one conceals the secret Path to Shambhala.
And that path shall only be revealed to the Pilgrim who bears the Golden Passport."The "Golden Passport" Marco speaks of is the Tibetan Phurba which Marco Polo included with the map. The dagger is for, as Drake describes, "destroying obstacles... y'know, spiritual ones". The markings on the Phurba dagger correspond to symbols found on the temples themselves, and by following the correct symbol, Nathan Drake was able to find the correct temple which concealed the "secret path to Shambhala".