1861 Pic 9: EIR 1/2 Mail Clearly Marked & hence oldest Running Train. HWH-BWN-Raniganj
Pic 2/3: GIPR: Mixed Service. Bombay-KSRA, Thul Ghat Convey, IGP-CSN * Bombay-Tillowlee, Bhore Ghat Convey, KAD-Pune/SUR
Pic 4: BB&CI: Mixed Service BL-AKV, Horse/Carriage, BH-BRC
Pic 6: Madras Railway: 1,2,3 Passenger MAS-Tripatoor. MAS DEP/ARR: 1861 6:15/20:31 MAQ Mail 20:20/5:40. With opposite schedule it cant be forerunner of MAQ Mail. 1861/1868 Pass...
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MAS DEP MAS @ 6:15/05:00 Malabar 1935 DEP 20:05. Malabar Exp & MAQ Mail together cant be successor of 1,2,3 Pass with opposite schedule (No M/E in MAS-MAQ till 1868 & i guess not before 1907. Till 1955 none 1/2 MAQ Mail click here but show up in 1960 click here Its oldest named train which still exist & 1/2 Mail existed in 1861 with Night/Morning HWH DEP/ARR like Kalka Mail!!

Presenting History Of My Most Favourite Train

The oldest running long-distance train of the Indian Railways, Punjab Mail, connecting Mumbai-Firozpur - originally linking Bombay with Peshawar (now in Pakistan) - turns 110 on Tuesday, Central Railway officials said here on Monday.
The Punjab Limited as she was called then, is a little over 16 years older than its more glamorous counterpart Frontier Mail,...
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though its origins are rather vague.

She steamed out of Bombay's Ballard Pier Mole station - which was the hub of the erstwhile Great Indian Peninsular Railways (GIPR), that later became the CR.
Based on a Cost Estimate paper of 1911 and a complaint by an irate passenger in Oct. 2012 about "the later arrival of the train by a few minutes at Delhi" station, the CR concluded that the Punjab Mail made her maiden run on June 1, 1912.
To begin with, there were the P&O steamers bringing in the mail, and excited officers of the British Raj along with their spouses, coming to their first postings in colonial India after a 13-day long sea voyage from Southampton to Mumbai Port.
Since the British officials held a combined ticket both for the sea voyage to Bombay and then onward inland journey by train to their place of postings, after disembarking they would simply board one of the trains from here bound for Delhi, Calcutta or Madras.

The Punjab Limited used to run on fixed mail days from Bombay to Peshawar covering 2,496 kms in around 47 hours along the Great Indian Peninsular route, via Itarsi, Agra, Delhi and Lahore.
At that time, it had only 3 passenger cars with a total capacity of 96 travellers, three for postal goods and mail, and was the fastest running train in the British India.
The passenger coaches were all corridor cars in first class, dual berth compartments, and well appointed with lavatories, bathrooms, a restaurant car, a compartment for the luggage and servants of the British officers.
Later, from 1914, the Punjab Limited started originating and terminating at the Bombay VT Station, now Chhatrapati Shivaji Maharaj Terminus Mumbai and a UNESCO World Heritage site.
Today, the journey time of Punjab Mail, hauled by electric engines, has come down significantly, covering the 1,930 kms between Mumbai CSMT-Firozpur Cantt in 34 hrs 15 mins.
Compared to the original 6 cars of the Punjab Limited, Punjab Mail now has 9 air-conditioned coaches, 6 sleeper coaches, 5 general second class coaches, a pantry and a generator van.
By mid-1930s, it also started catering to the Indians on the move in Third class cars, it got the first airconditioned coach in 1945 , from May 1976, it was hauled by diesel engines, and by 1980s with electric engines as a large part of the trunk routes on the IR network got electrified.
From December 2020, the Punjab Mail started its journey with the German-designed Alstom LHB GmbH's Linke Hofmann Busch (LHB) coaches which give more safety and a pleasant travel experience to the passengers.

Source - click here