Mud (also known as Mudh and Muth) is a small village in the cold desert region of Spiti in Himachal Pradesh, India.

He made Mud the base for his fieldwork on the geology of the Western Himalayas and named an important geological rock layer stretching from Kashmir through Spiti to Nepal in the Western Himalayas, calling it the Mudh (Mud) Series.

[2] This remote village at the upper end of the Pin River Valley, surrounded by inhospitable mountains, thus attained prominence.

[3] G. Fuchs wrote: "The pioneering work by Stoliczka, Griesbach, Von Krafft, Dlener, and Hayden has made Spiti famous as a classical geological area of the Himalaya, particularly of the Tethys or Tibetan Zone.

"[1] After a gap of many decades after Hayden's 1899 visit, in July – September 1978, an Indo-Austrian expedition led by G. Fuchs (Geological Survey of Austria) and D.K.

Bhatt (Geological Survey of India) did fieldwork on the Mudh Formation in Mud and nearby places.

[4] Subsequently, Indian geologists Parcha and Pandey from the Wadia Institute of Himalayan Geology, Dehradun, visited in about 2011.

The village is at the base of the towering Pin Parbati range that separates Spiti from Kullu district.

As vegetation is sparse, the rock strata in the steep cliffs are easily visible to the geologist, without excavation or drilling.

[1][4] (mya) The Muth Formation is readily observed in the Farakah Section, north-west of Mud village.

These indicate that it originated from coastal sediments deposited in a wave-dominated barrier island system in the Tethys Sea.

The neighbouring formations, Pin (lower, i.e. older) and Lipak (upper, i.e. younger), have body fossils that are accurately dated.

Located at a high altitude with the upper reaches being largely unexplored, the area is home to several endangered species including the snow leopard.

These include Ibex, Chhumurthi horse, Bharal, Red fox, Marten, Weasel, Pika, Snow Cock, Bearded vulture, Chukor, Golden Eagle, Griffon, Yellow-billed Chough, Raven etc.

Harish Kapadia reported that local people traveling to Shimla for business or studies would prefer the short trek over the Pir Bhaba Pass to the uncertain 254 km (158 mi) road journey via Tabo.

[7][19] During the summer, public buses and private vans ply regularly from Kaza to Mikkim and Mud in the Pin valley.

Then, the approach to Mud is via private vehicle and foot from Attargo bridge off NH-505, a distance of 33 km (21 mi).

The new 72 km (45 mi) road will run from Kafnu (NH-5) in Kinnaur to Mud, connecting to NH-505 near Atargu Bridge on the Spiti river.