Originally called Church Stanton, RAF Culmhead opened as a three-runway fighter airfield on 1st August 1941, and was later renamed to avoid confusion with Church Fenton in Yorkshire. Also known as Tricky Warren, presumably because it was built on the land belonging to the farm of the same name. Some of the farm buildings were utilized for the airfield.
RAF Culmhead was one of three WW2 airfields situated close together on the beautiful Blackdown Hills, the other two being Upottery(Smeatharpe) and Dunkeswell.
It began it's life as an emergency landing ground and dispersal airfield, and was also used as a base for the testing of barrage-balloon wire cutters. As a fighter base for Spitfires and Hurricanes, it was occupied by No 2 Polish Fighter Wing and later by Czech units. English pilots were also based there. The fighter planes protected our bombers crossing the channel and also intercepted and shot down enemy aircraft over our country.
Following D-Day it was used for training the first jet-engined aircraft in RAF service. This comprised two Meteors, which arrived in July 1944. There was very little activity other than that, and was subsequently closed in August 1946.
Walking from the suggested parking you cross two of the original runways. At the GZ you can see the original control tower to the North. If you continue down the lane past the GZ for a short distance you can see some of the original buildings stll remain and are protected by law.
If you are trying to orient yourself using the map here is it very confusing! The map itself at GZ is oriented North but pointing South!

This image shows the airfield from the air. If you park at suggested parking you cross on the path you can see on this image from left to right in the upper third.
The cache is a magnetic key safe - with a £1 for the FTF!
There are a few other caches nearby on both this airfield and the other local ones that are worth checking out.