Calf Top

Summary

Calf Top is a mountain in the western part of the Yorkshire Dales, England. It is located in the county of Cumbria, although Lancashire and North Yorkshire are not far away. Calf Top is a dominating profile in the view from many of the smaller hills to its west, such as Lambrigg Fell and Hutton Roof Crags.

Calf Top
Highest point
Elevation610 m (2000 ft)
Prominence312 m[1]
Parent peakWhernside
ListingMarilyn, Dewey
Coordinates54°15′55″N 2°31′00″W / 54.265178°N 2.516612°W / 54.265178; -2.516612
Geography
LocationYorkshire Dales, England
OS gridSD 66449 85624
Topo mapOS Landranger 98

Calf Top is separated from its neighbours, Great Coum and Aye Gill Pike by the deep trench of Barbondale, meaning that although it is lower than most of the hills in its region, it has high relative height and is a Marilyn.

Status as a mountain edit

The height was formerly shown on Ordnance Survey maps as 609 metres. The closeness of this figure to the threshold of 2,000 feet (609.6 m) used in the United Kingdom to separate mountains and hills led to the summit being surveyed using precision GPS and levelling equipment.[2][3] The height was found to be 609.58 ± 0.1 m, or fractionally below 2,000 feet. The result was discussed with the authors of the Nuttalls, Hewitts and Deweys who all agreed that the hill should retain its current status as a member of Dewey's list of hills at least 500 metres but less than 609.6 metres high.[4] Current OS maps show the height rounded to 610 metres.

The Ordnance Survey recalculated the height of the mountain in 2016 when the authoritative definition of the British national height datum, Ordnance Datum Newlyn, was transitioned from the OSGM02 geoid model to the OSGM05 version, causing a general upwards shift of 25mm in orthometric heights.[5] This resulted in a height of 609.606 metres, thus updating the status of Calf Top from hill to mountain.[6][7]

References edit

  1. ^ "Database of British and Irish hills v13.2". Hills Database. Archived from the original on 5 August 2018. Retrieved 28 August 2013.
  2. ^ "Survey of Calf Top" (DOC). Hill Bagging. 27 April 2010. Archived from the original on 14 April 2021. Retrieved 10 December 2022.
  3. ^ "Second Survey of Calf Top" (DOC). Hill Bagging. 27 July 2010. Archived from the original on 14 April 2021. Retrieved 10 December 2022.
  4. ^ "Is Calf Top a new 2000ft mountain?". Hills Database. 2016. Archived from the original on 7 December 2021. Retrieved 10 December 2022.
  5. ^ Greaves, Mark (2016). "OSGM15 and OSTN15: Updated transformations for UK and Ireland" (PDF). Ordnance Survey. Archived (PDF) from the original on 14 August 2022. Retrieved 9 December 2022.
  6. ^ "Calf Top Cumbrian hill re-categorised as a mountain". BBC. 2016. Archived from the original on 9 December 2022. Retrieved 9 December 2022.
  7. ^ "OSGM15 - the new geoid for Britain". Ordnance Survey. 2016. Archived from the original on 10 December 2022. Retrieved 10 December 2022.