These towers were built to a standard design and made of precast concrete sections and referred to by the abbreviations "BT 9" or "BT 11" - the older Type 11 was cylindrical; the later Type 9 had a rectangular floor plan. They varied in height depending on local circumstances and were accessed through a steel door that was usually hidden from the direction of the border. Offset metal ladders led via two or three intermediate corrugated steel floors to the top. The main observation deck was equipped with seating, rifle racks, an air filter system, signaling equipment, log book, mapping material, dedicated communications to the border reporting net, electric heating and emergency and rescue equipment including abseiling kit. It had room for 4-5 soldiers who, usually, formed the "Warning Group" (Alarmgruppe) The roof terrace was protected by a steel pipe railing and could be accessed through a lockable, airtight steel hatch. On the roof was a movable, remotely operated searchlight (elevation -/+ 90 degrees, azimuth 360 degrees).
|Wikimedia Commons has media related to Border watchtowers in Germany.|