The Delhi-Umballa-Kalka Railway(DKR) Company was formed in 1889. The broad gauge(BG) line ran north from Delhi via Umballa +(Ambala)+ to Kalka in the Himalayan foothills where there was a connection to the DKR owned Kalka-Simla Railway narrow gauge(NG) line that opened in 1903  .
+ Umballa is used in this text as it was the name of the Railway Company.
+ Amballa and Ambala are also recorded in different documents as various spellings .
Refer to FIBIS Fact File #4: “Research sources for Indian Railways, 1845-1947” - available from the Fibis shop. This Fact File contains invaluable advice on 'Researching ancestors in the UK records of Indian Railways' with particular reference to the India Office Records (IOR) held at the British Library
An on-line search of the IOR records relating to this railway  gives 23 references. The most important being:-
- L/F/8/13/945/1 “Delhi Umballa Kalka Railway Company Limited, Contract for the construction of the Delhi Umballa Kalka Railway; 1889”
- L/AG/46/9 “Records of the Delhi-Umballa-Kalka Railway Company; 1898-1907”
- L/AG/46/29 “Records of the India Office relating to the Delhi-Umballa-Kalka Railway; 1889-1926”
There are no Personnel Records held in the IOR
There are limited references in other documents:-
- Alexander Izat joined the Board of the Delhi-Umballa-Kalka Railway(DKR) Company in 1902, and also the Kalka-Simla Railway Company. This in addition to being a Director of the Rohilkund and Kumaon Railway(R&KR) from 1883. He retired from India in 1904 .
- Robert Atwell Way, Executive Engineer from the Public Works Department - State Railways as 'on loan to the Delhi-Amballa-Kalka Company in 1889' ; this is confirmed by the 1890 Civil List .
- Herbert Septimus Harington was Chief Engineer of the DKR and also the Kalka-Simla Railway from about 1904 to 1908 .
- Delhi-Kalka Line" Wikipedia
- British Library “British Library Archives and Manuscripts Catalogue” - Search; Retrieved 20 Jan 2016
- " Administration Report on the Railways in India – corrected up to 31st March 1918"; Superintendent of Government Printing, Calcutta; page 60; Retrieved 24 Dec 2017
- " Administration Report on the Railways in India – corrected up to 31st March 1918"; Superintendent of Government Printing, Calcutta; page 60; Retrieved 14 Jun 2020
- IOR "Records of the Delhi-Umballa-Kalka Railway Company" IOR/L/AG/46/9"; Retrieved 14 Jun 2020
- US Archive .org pdf download of ‘History Of Indian Railways, constructed and in progress’, 31 March 1937 by ‘The Government of India – Railway Department’ page 151 pdf 190; Retrieved 14 Jun 2020
- Grace's Guide "Alexander Izat"; Retrieved on 7 Jul 2016
- Google Books " India List and India Office List, 1905" page 642 (pdf page 605 ) Retrieved on 18 Jul 2016
- “India Civil List” 1890, page 41
- ‘Grace’s Guide/Inst of Mechanical Engineers Obituary 1914’ “'Herbert Septimus Harington” Retrieved on 21 Nov 2018