Ranikhet Express - रेगिस्तान में हरियाली

Reason for naming as Nilgiri Express:
Source: Etymology of train names
2671/ 2672 Chennai Central – Mettupalaiyam (SR Salem division)
The Nilgiri Express (also known as the Blue Mountain Express, or Nilagiri Express) is named after the Nilgiri (Tamil, English - Nil - Blue; Giri - Mountain) Hills. The train is primarily intended for travelers to these hills, especially to the towns of Ooty, Coonoor...
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and Kotagiri. Mettupalaiyam is at the foot of these hills, and the Nilgiri Express links to the Nilagiri passenger train operated by the Nilgiri Mountain Railway (NMR) at Mettupalaiyam station, enabling passengers to complete the journey to Udhagamandalam (Ooty) by rail.