Mao said "this will be the mother of partisans" between mountains in the province of Shaanxi.
In the valley there was the Yellow River. Has reached that place with just eight thousands soldiers (from the orignal 50k).
Has called also the yellow valley because ocra-yellow is the dominat colour because the presence of sands brought from Mongolia.
The long March has finished reaching in Loess, and for others ten years will be the capital of communist chinese party, in Yanan.
An area of over 30k km square, with over 1 million citizens.
Chinese mitology will say that Yanan was the cot of china, and in part is true, infact between these valleis emerged Xia dinasty and also Gengis Khan with his army and always here was the first place of the first civilization during
neolithic period.
However Yanan is the perfect place for its strategic position for many reasons (we will discover why*) and that megalomaniac mao will call it "the bottom of the red revolution".
Yanan is surrounded by natural mounts and hills, engraved by winds and natural forces, and now it is a natural fortress with high walls.
The communist army transform that citadel an inexpugnable town, and why?
*Because the peculiarity of Yanan is to get hundreds of "yaofang" →cave houses that became houses of communists heads, like Mao Zedong, and yes the same of Xi Jinping (during his youth eh eh, yeah is not a coincidence).
Mao, during 1935 after enlarged his army (bigger and with better equipments) opened some ways near to russians borders, because his first idea was to get some reinforcements from communists of russia or just a safe way to escape from nationalists.
Infact to any head of a communist tribe that have loyalty to Mao was assigned a safe way via yaofang that reached russian border.
You can get a testimony of these yaofang of yanan from a book "Red star over China" of Edgar Snow. (or also from the famous book of Kai Vogelsang).
However in short Snow met in 1936 that idiot, and describe him like a pious man, when in reality he wasn't and seeing boobs of chinese women and drinking some spicy tea,
he wrote stupid things for his useless book, and good stuff for CIA (yes was a secret agent) and infact in secret describe eleven, E-L_E-V-E-N secret tunnels that put connections Yanan to russia.
Infact all them were used in 1954 from USA army (wanted by CIA) to give indipendence to Tibet without success (and also in 2005-6 from Bush junior with the help of that idiot of actor friend of dalai-lama)
Times ago were used to ship saffron-nutmeg-sterculia urens (a drug with same peculiarity of gugul a nepalian tree, yeah Google took the name from it aand not from igloo).
After all these shits infos,another stupid wall of text, and taken attentions from all you, I can leave my kinki pillow positions and return in my normal life.