MOD Aberporth

If you intend to cruise or sail in the south of Cardigan Bay please look at the activity scheduled at MOD Aberporth. This information is available on their web site. The Range Danger Area covers 6,500km2.  The weekly activity is available on their web site - 



The MOD Aberporth Range has a Sea Danger Area which covers a large part of Cardigan Bay, so before setting out on any trip into the bay you are strongly advised to familiarise yourself with area. Please refer to the map (shown right) or the co-ordinates page for full details.

Normal Range operating hours are 09:00 hrs until 17:00 hrs Monday to Friday but it does occasionally operate outside these hours and can include weekends. Activity varies on a daily basis and although there will be opportunities to transit through the Danger Area safely, please note that it is a live firing area and for your own safety you will need to contact the Range using one of the methods below:

Range Control : 01239 813480
Marine Control : 01239 813760
IMM Channels : 16 & 11


A Range programme is produced every Friday and sets out the schedule for the following week – Click here to view latest version. Your safety, and that of the Range users, is of paramount importance and while Range Control can advise you on which are potentially the best days to transit the Danger Area. Please note that that the programme can be subject to last minute changes due to unforeseen circumstances. The nature of the activity on the Range, combined with the weather conditions on the day may help, hinder or delay your safe passage.

The key challenge for the Range operators is being made aware of your presence. While the temptation may be to revert to stealth tactics and ignore the warnings, to do so could place you and others at serious risk to life and limb.

Following the ‘Do’s and Don’t’s’ guide below should help you have a safe and hazard free passage.


  • Contact Range Control (Tel: 01239 813480 or VHF Channels 16 & 11) a few days ahead of your intended crossing to discuss your proposed route and to ascertain good and bad times to cross.
  • Contact Range Control on the day to confirm your intentions, likely time of entry & exit and to ensure there have not been any changes to Range activity since your previous call.
  • Contact the Range when you exit.
  • Recognise that the Range has a programme to deliver – flexibility and clarity on all sides is the key to safety.
  • Make fellow mariners aware of this message!


  • Assume that sticking close to the coast and not contacting Range Control will keep you out of harm. There is a reason why its called a Danger Area!
  • Assume that the Danger Area is safe simply because you can’t see or hear any activity.
  • Press on regardless if you have been advised it is not safe to enter.
  • Don’t forget to contact Range Control when you exit.


A military testing range was first established in Cardigan Bay during the Second World War. The Range is controlled from a site near Aberporth and is known as MOD Aberporth. Over the years the Range has played a significant part in the development and testing of a variety of military weapons.

Today MOD Aberporth provides a large secure safety area for the testing of air launched weapons and Unmanned Aerial Systems (UAS). Their web site now provides information about activities undertaken at MOD Aberporth to those who work and play in and around the Cardigan Bay area.

MOD Aberporth Facts and Figures

The site comprises approx. 550 acres of main operating base located at Aberporth and employs some 200 people who work there in direct support of the Range operation. The Range is a significant employer in the West Wales area and working with local communities is an important part of our successful operation.

The Range Danger Area covers some 6,500km^2 of Cardigan Bay from sea level to unlimited height. To supplement the safe operation of the Range, there are a number of small outposts located on the edge of Cardigan Bay and the Llyn Peninsula. These outposts contain equipment that enables the Range to effectively assess the performance of weapons.

Article updated 29/09/2020