The Silk Road
It was the great German geographer Ferdinand von Richthofen in 1877 to use for the first time the term Silk Road. It became in time a network of approximately 8,000 km of routes by land, sea and river, crossed by caravans from Xi'an (China) crossing through Asia, the Middle East and even reached Korea, Japan and India. Silk arrived in Rome that was unaware of the composition and origin.
On the Silk Road traveled goods but also great ideas and religions, trade and cultures of great importance to the development of the civilizations of Egypt, China, India and Rome for the foundations of the modern world.

Historical Silk Routes
Some historical silk routes partially overlapping to the tourist route (green) can be here highlighted or hidden by clicking their names:
-- The ancient north silk road (blue);
-- The Loulan Route (red);
-- The Kashgar-Ladakh-Kashmir Route(yellow);
-- The Karakoram Way (red);
-- The South Buddhist Way (pale blue);
-- The Battriana Route (red).
-- Marco Polo between 1271 and 1295 undertook a journey from Venice to the East of China, then south to Malaysia and then followed the west coast of India, the Middle East and the Mediterranean Sea. Here, highlight in orange, there is only the 'small' route through the north of China;

The Xian - Kashgar (green) is one of the Silk Roads which continues on the Karakoram Highway.

The Kashgar - Rawalpindi (Karakoram Highway) (orange) is the highest international tarmac road in the world; connecting China to Pakistan through the Karakoram mountain range, surpassing the Khunjerab pass at 4693 meters.
It connects the north of Pakistan to the ancient Silk Road in about 1,200 km from Kashgar (Xinjiang, China) to Havelian in Abbottabad district in Pakistan. The continuation of the road meets the Grand Trunk Road at Hasan Abdal, west of Islamabad.

Buddhist testimonials in Xinjiang
Xinjiang is the Chinese name for the Tarim and Jung regions in contemporary north-western China, and is historically known as Serindia; it has many Buddhist shrines dating from the 5th to the 12th century with paintings of great value.
Buddhism, born in India in the sixth century BC, was the first major religion imported into China. From the 3rd century, Buddhism began to enter in the aristocracy of the empire, especially in northern China, and developed a large religious and cultural exchange through the tracks of silk caravan of Central Asia.
Later the Annals of the Wei dynasty recall that in 518 AD more than 30 thousand monasteries and temples were built in China.
Like other religions, also the Buddhism in China experienced various vicissitudes, from periods in which enjoyed the protection of the leaders in times of persecution by the emperors and bureaucrats who preferred Taoism.
Buddhism reached its peak in the Tang dynasty, which reigned from sec. VII to the beginning of X. But it was an emperor of this dynasty, Wuzong (840-'46), to proscribe Buddhism with an edict ('845) with consequent destruction of monasteries.
Since sec. X then begins a phase of slow decline.
This site shows some places where there are important evidence of Buddhism.