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Name:Flat Holm
Hill number:18652
Height:32m / 105ft
Parent (Ma):none
RHB Section:32C: Neath to Chepstow
County/UA:Cardiff (UA)
Island:Mono Tump island
Maritime area:Bristol Channel
Class:Tump (0-99m), SIB
Grid ref:ST 22259 64657
Summit feature:no feature: ground by lighthouse battery
OS map sheet(s):(1:50k) 171 182
(1:25k) 151E 153
Observations:ground by magazine W of lighthouse at ST 22198 64672 is probably lower
GPS data:show GPS entries for this hill

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To contribute a summit or portrait photo for a hill
please contact the hillsummits website

N.B. Some hill summits are on private property or on land where there is no public right of way.  Permission should be sought from the landowner where access to a hill summit is through private land.
Please report via the contact page any logs you see below which describe or encourage acts of trespass, and mention the hill number and hill name.

Logged Descriptions  (logged by 23 users)ByDate of Ascent
Bagged during an ALK (Association of Lighthouse Keepers) organised trip. Got inside lighthouse, ascended well above the island summit and got great views from the lamp room. Walked over all potential high spots of natural land.assynt_bob30/09/2018
Great trip with Bay Island Voyages RIB from Cardiff Bay with Paul Webster. Island warden and assistant did a great jog plus enjoyed a shandy and a black coffee in the most southerly pub in Wales.Dugswell222/08/2018
On the RIB. Good fun at speed. Island warden and staff provided a free tour of the island. Well worth staying with this. High point next to huge Victorian gun barrel. Cardiff completed.Campbell Singer17/08/2018
Interesting island. Two hour visit was excellent. RIB was great fun.Jemma Singer17/08/2018
With Cardiff Sea Safaris on a chilly sunny Nov morning, thru the Barrage lock then a sprightly 10 minutes 28 knot crossing, highest point near lighthouse, indeterminate due to gun emplacements. My final Cardiff UA Tump, with Andy W and assorted localsRHW26/11/2017
With Cardiff Sea Safaris. Great trip. Highly recommended. Cardiff completed & my 2,999th Tump. Hoping to reach 3,000 on Arran next weekend.ngthack12/11/2017
Day trip from Penarth Pier on the Westward Ho, 4 hours on Island, most Southerly point in Wales is here, gulls had headed South to Africa. Well worth visit with guided tour of Island. Great viewsPeterD17/09/2016
Day trip on ferry from Penarth near Cardiff. Great place to visit, so much history!Swindon Bagger06/08/2016
Day trip from Cardiff on the Westward Ho. Gulls feisty.summitsup06/06/2016
£30.00 boat trip from Cardiff.arranc15/05/2016
Used Cardiff Sea SafarisAdrian06/12/2015
Day trip from Cardiff Bay. Lovely day with calm sea. Summit adjacent to lighthouse by remains of gun battery.Ramblingpaul06/09/2015
Day trip on Westward Ho from Cardiff. Bit of a slog to summit, but we made it! Lovely warm sunny day watching severe thunderstorms passing N and S but leaving Bristol Channel clear. Highest point was atop Victorian magazine few metres W of lighthouse (itself an OS intersected station).jonglew28/06/2014
On a Cardiff Council Christmas visit. A magical spot. Very pleased to be the first bagger on this site too!huwthomas15/12/2012
Several visits from Weston-Super-Mare on the White Funnel paddle steamers.richtea5040blank
Alan Whatley14/07/2019
Alex C22/09/2018
Tony J01/07/2014
Margaret blank