A ballast pond was a construction found in shipyards during the age of sail. The feature was often a prominent part of the large dockyards of the Royal Navy, where large numbers of warships would be laid up 'in ordinary' during periods of peace, when the navy retained only some of its ships in active commission. Ships in ordinary often had their stores and guns removed, as well as their masts. Consequently, their ballast, often made up of varying quantities of stone, was increased to compensate. When the ships were reactivated, and fitted with stores and guns, large quantities of ballast was removed.