IWM caption : "'Boche-Buster', a 250-ton 18-inch railway gun, <a href="https://en.wikipedia.org/wiki/Catterick_Garrison" class="extiw" title="en:Catterick Garrison">Catterick</a>, 12 December 1940. The gun later travelled down to Kent to take up position at Bishopsbourne on the Elham to Canterbury Line, taken over by the Army for the duration."<br>
The gun was in fact an <a href="https://en.wikipedia.org/wiki/BL_18_inch_railway_howitzer" class="extiw" title="en:BL 18 inch railway howitzer">18 inch howitzer</a>.
Photographer: Kessell (Mr) War Office official photographer
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<td>This photograph <a rel="nofollow" class="external text" href="https://www.iwm.org.uk/collections/search?query=H+6089">H 6089</a> comes from the collections of the <a rel="nofollow" class="external text" href="https://www.iwm.org.uk/">Imperial War Museums</a> <small>(collection no. 4700-37)</small>
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<td align="right"><img alt="Flag of the United Kingdom (3-5).svg" src="https://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Flag_of_the_United_Kingdom_%283-5%29.svg/80px-Flag_of_the_United_Kingdom_%283-5%29.svg.png" decoding="async" width="80" height="48" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Flag_of_the_United_Kingdom_%283-5%29.svg/120px-Flag_of_the_United_Kingdom_%283-5%29.svg.png 1.5x, https://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Flag_of_the_United_Kingdom_%283-5%29.svg/160px-Flag_of_the_United_Kingdom_%283-5%29.svg.png 2x" data-file-width="177" data-file-height="106"></td></tr></tbody></table></div>