The signal station at Carrowmably is located close to the edge of a hill over looking a narrow coastal plain. The signal station consists of a very well preserved signal tower that is set within a large pre existing oval enclosure. The site has extensive views in all directions although none of the adjacent signal stations can now be seen; Rathlee Signal Station to the west is obscured by trees and Knocklane Hill Signal Station to the north east is only a low ruin. The signal station is approached via a lane that leads north through the dispersed settlement of Carrowmably but lies on farmland and permission must be sought before visiting the site.
The signal tower at Carrowmably is arguably the best preserved example in Connacht. The tower is aligned with the first floor doorway on the northern wall, windows on the east and west wall and the chimney on the southern wall. Almost all of the cut stone work is intact around the windows and doorway, the cut stone coping stones and the top of the walls are intact.
The striking machicolation over the door is almost complete, missing just a little stone work from the top of the eastern side. Given the excellent preservation of the machicolation over the doorway the small rectangular gap is worth considering. Similar gaps exist on the sides of the machicolation. Could these be a small gun loops? Gun loops are not present at any of the other signal stations in Connacht, but the bartizans at Carrowmably also feature similar gaps.
The opening up of the northern ground floor window on the eastern wall allows for ground level access to the interior of the tower. This is a common solution seen at most of the signal towers that survive to close to their full height. How much such openings weaken the structures integrity is an interesting question given how many of the signal towers have collapsed. It is not known when the northern first floor window was closed up with stonework, but the northern window on the western wall was also blocked up. It is tempting to think that the officer who resided on the first floor felt that two windows were all quite sufficient.
The bartizans on the southern corners feature possible gun loops on both outwardly facing sides and on the return angles facing onto the adjacent walls.
The southern wall features the characteristic bulge that houses the chimney but only a single stone belonging to the chimney stack can not be seen from outside the building. The pair of large stone blocks built into the wall at this point suggest that the wall may have been strengthened in order to support the weight of the chimney stack. Given the excellent state of the signal tower the complete lack of external render is worth mentioning. It is possible that this tower did not feature exterior render and slates.
Inside the tower there are all of the expected features, including the largely infilled semi-basement, the fireplaces and alcoves, the split mezzanine level between the ground floor and the first floor, the small attic over the first floor and the entrances to the bartizans and the machicolations.
It is important to note that, in contrast to the exterior, the interior walls feature large areas of render on the walls.
The parapet wall, above the joists for the roof, was stepped back from the main face of the internal wall. The bases of the bartizans and the machicolations consisted of thin stone slabs.
The signal tower is set within a large oval enclosure defined by a very large earthen bank with a deep internal bank, suspected by some archaeologists to be a massive Neolithic Henge. A smaller circular enclosure is present within that enclosure, which might represent an earlier period of reuse as it strongly resembles a ring fort.