Why have they got ANTI-AIRCRAFT GUNS protecting this runway?

Not the most welcoming of grass strips with anti-aircraft guns protecting final approach. My name is Terry Kent and I am a General Aviation PPL private pilot operating out of Andrewsfield Airfield EGSL about 25 miles to the north east of London in the UK. Short Field is my little channel focused on the lighter side of General Aviation including flight and airfield reviews, equipment unboxing and review plus all things private pilot related. I use various cameras to record my videos including GoPro and Insta 360 and stills and edit them in Adobe Premiere Pro, I am an animator as well and often use animations to describe situations more clearly I use Blender and Adobe After Effects for these. I always attempt to post my videos in the highest possible quality, normally 4k. I fly a 2011 Pipersport two seat single engine aircraft that is also known as the PS28 or SportCruiser in the USA (America) it is know under the FAA as an LSA or Light Sport Aircraft and can be flown on a very basic license. In the UK it is a Part 21 airplane which requires a full licence but it's generally cheap to run, affordable maintenance and great value for money. It cruises at 100 to 105 knots and has superb short take off and landing or STOL capabilities. I visit farm strips, back country and short airfields, some of them dangerous and I try not to crash :-), as well as international airports and try to learn something new every time I fly. I fly VFR and IFR as well as visual and instrument approaches. My videos may give helpful information to pilots but please remember these are just for entertainment, I am not an instructor nor should anything shown in my videos be used for real world aviation, also the airfields I visit may have totally changed or even closed since the making of the video so always consult the latest information for your country. If you enjoyed this video, please give it a ‘thumbs up’ and leave me a comment in the box below, I love to read them and I also like to hear what you like or dislike about my video. Please share it with anyone you think would be interested and I'd so love it if you ticked SUBSCRIBE and DING THE NOTIFICATION BELL to be informed by YouTube when I upload my next video. Thank you so much. If you are interested, my video content is available to purchase as stock footage, please contact me via my email address in the ABOUT section of my channel for more information. If you like my content (I don't get any revenue from this channel at all) you could buy me a coffee but no worries if you don't want too, I'm just chuffed that you are even interested in my videos, and if you ever see me at any airfields please come over and say 'Hi' and I'll probably buy you a coffee. https://www.buymeacoffee.com/shortfield If you see me around please, please come over and say 'Hi'. Planning Software: SkyDemon https://www.skydemon.aero/