Tim Carey on Twitter: "Map of the sites of the 16 original Martello Towers and gun batteries between Bray and Sandymount and their 1600m arcs of fire. Built from September 1804 to
![UNESCO World Heritage Centre - Document - Burnt Point Fort, Martello Tower, Ferry Reach Magazine, Ferry Island Fort UNESCO World Heritage Centre - Document - Burnt Point Fort, Martello Tower, Ferry Reach Magazine, Ferry Island Fort](https://whc.unesco.org/uploads/thumbs/UK-983-020,%20021,022,023-500--20100827175118.jpg)
UNESCO World Heritage Centre - Document - Burnt Point Fort, Martello Tower, Ferry Reach Magazine, Ferry Island Fort
![Carleton Martello Tower National Historic Site Walking And Running Trail - Saint John, New Brunswick, Canada | Pacer Carleton Martello Tower National Historic Site Walking And Running Trail - Saint John, New Brunswick, Canada | Pacer](https://cdn.pacer.cc/route/screenshot/f8112_20200225_7.png)
Carleton Martello Tower National Historic Site Walking And Running Trail - Saint John, New Brunswick, Canada | Pacer
![Fingal County Council on Twitter: "Fancy exploring Castles, Round Towers, Heritage Houses, Martello Towers & more? https://t.co/1xF1rGZnQ9 #Dublin https://t.co/2jqNj0iB5f" / Twitter Fingal County Council on Twitter: "Fancy exploring Castles, Round Towers, Heritage Houses, Martello Towers & more? https://t.co/1xF1rGZnQ9 #Dublin https://t.co/2jqNj0iB5f" / Twitter](https://pbs.twimg.com/media/CjyAIZKUYAI7wZT.jpg)