Minefield numbering

The identification system is somewhat erratic; minefield serial numbers are prefixed either by 'MB' or 'MC'. It would appear that the 'M' stands for 'Minefield' followed by the Sub-area letter that the field was in. It should be noted that Sub-areas were a 1940 system and the boundaries changed when 55 Division took over East Sussex in 1941. Sub-areas became known as Sectors and the latter covered a smaller area due to there being more troops available in defence.

1940 Sub-Area	Coastal Extent (E-W)	1941 Sector	Coastal Extent (W-E)
A	Dymchurch (Kent) to Camber	A	Telscombe Cliffs - Cuckmere River
B	Camber - Norman's Bay	B	Cuckmere River - St. Leonards
C	Norman's Bay - Telscombe Cliffs	C	St. Leonards - Camber

Therefore, any MB field will be located somewhere between Norman's Bay - Camber and MC fields west of Norman's Bay. This numbering system appears to have been retained and continued even after the Sub-areas were reorgansied into Sectors.

There also exist large gaps within the numbering system. It appears that the MB and MC numbers remained as separate sequences up to a point.

The MB system seems to run up to at least 77 (with 33 numbers as yet unaccounted for), while MC runs from 1-12 (missing no.9 at this point), with the next number being 50.

My theory is that MB 1-77 and MC 1-12 were the original minefields and were perhaps allocated numbers increasing from west to east (There seem to be one or two exceptions to this idea, so it may not hold water.) I think then that new sequences were started at:

• MC 50 (MC 50-56)
• MC 101 (A-K)(perhaps sequence began at MC 100?)
• MC 150 (MC 150-154)
  
  
• 200 (200-228 - see below)

It appears that a 'fresh start' might have been made at the above numbers as new units took over sectors and new minefields needed to be laid. The new sequences introduce obvious gaps in the numbering to disassociate them with the original system and it may be that each of the three battalions in a particular brigade were allotted a range of numbers (starting at 50/100/150) they could use for minefield identification.

The final new sequence starting at 200 combines the MB and MC series, ie numbers are not duplicated between MB and MC, but give an unbroken run from 200-228 as follows:

• MC 200
• MB 201
• MC 202-203
• MB 204-205
• MC 206-208
• MB 209
• MC 210-211
• MB 212
• MC 213-222
• MB 223
• MC 224-228.

So with a collection of minefields numbered between 1 and 228 (with 19 duplicates due to the original MB/MC sequences) I think there were at least 150 minefields (including 19 that are suffixed A, B, C etc) in A, B and C Sectors.

Missing minefields

A worrying concept is that of uncharted minefields; a case in point being minefield MC 56 at Cuckmere Haven. A plan of the minefield dated April 1941 still survives in the archives. A map trace of late June 1941 confirms its location and identity, yet the August 1941 list does not mention it. I've seen no record of it being removed by the Royal Engineers before August 1941, or, indeed, any reason for it needing to be removed so soon after being laid. It looks as though despite the fact that MC 56 was mapped (and I have this information today), whoever compiled the Minefield List seemingly was unaware of MC 56, and so it was not included; a potentially disastrous state of affairs. My research has revealed that a Sapper was killed whilst laying a minefield (quite possibly MC 56 itself) at this time.

I'm compiling a list of minefield numbers that are not in the 1941 list; as will be seen on the database page, some of these were actually assigned to minefields that were proposed but seemingly never laid. The November 1940 defence scheme for Rye shows several proposed minefields that don't appear on 1941 maps or the minefield list; it may be that these numbers were never used on laid minefields to avoid confusion or tragic accidents.