Halifax's defences underwent a complete re-assessment in the 1860's as a result of deteriorating relations with the United States and rapidly changing military technology. The age of sail and smooth bore guns had come to an end and were being replaced by steam power, armour plate and rifled guns. To meet the new challenges, old forts were being rebuilt and new ones planned. Among the new forts was Fort Ives, at the northern end of McNabs Island.

In 1865, work began on Ives Point Battery on the site that was initially cleared in 1762 following the loss of St. John's. Built to protect the inner harbour channel between McNabs Island and York Redoubt/Point Pleasant, the original fortifications incorporated the newest advances in British coastal defence. It was a typical RML (Rifled Muzzle Loading) fort with two faces. The southwest face mounted three 10-inch RML's and covered the waters between Maugher Beach and York Redoubt (Figure 21). The west face mounted five 9-inch RML's and covered the channel toward Point Pleasant. A sixth 9-inch RML was mounted at the salient where the two faces met. The rear of the fort was enclosed by an earth parapet and a wooden palisade. An enemy attempting to reach the inner harbour would face a devastating broadside from Fort Ives. In many ways the fort was the linch-pin that knitted together the inner and outer harbour defences. The guns were in open emplacements protected by iron shields, making them unique in the defence complex.

Given its strategic location it is not surprising that Fort Ives underwent modifications to keep pace with technological improvements. The first improvement took place between 1888 and 1892 when breach loading guns were introduced. Much of the alteration was associated with Fort Ives' increasing importance to the submarine mining system for the harbour. The main field was located in the strategic channel between Ives Point and Point Pleasant. To protect this channel against enemy attack the British introduced light Quick Fire (QF) guns. A battery of three 6 pounder QF's was constructed just north of Fort Ives' palisade in 1890-91. Indicative of Fort Ives growing importance to the mine field were the construction of a test room and observation station by 1898.

This was only the beginning of modernization at Fort Ives. New breach loaders on central pivot mountings were introduced on the west face of the fort. The only RML's left were those on the southwest front and they had become obsolete. The new guns included two 6 inch BL's and two 12 pounder QF's. When completed in 1903 the fort had both counter bombardment and close defence responsibilities. Much of the new construction was related to Fort Ives' important role in mine defence. Searchlight (EL) emplacements were constructed to complement the 12 pounder QF's in providing protection to the main mine field.

When Canada assumed responsibility for the Halifax defences in 1906 a complete re-assessment was initiated. By this time the importance of the mine field had lessened. The chief threat was perceived to be light, fast torpedo boats. To meet this threat it was decided that the Quick Fire and searchlight defences at Halifax should be concentrated in the vicinity of the strategic Ives Point/Point Pleasant channel to prevent access to the inner harbour. All agreedthat the illuminated area in front of Fort Ives had to be enlarged. By 1912 four permanent searchlight emplacements with support facilities had been constructed.

Ives Point Battery was one of the more important components of Halifax's defences during World War I. The fort's electric lights were the only dispersed beams available for illumination of the main channel until the fall of 1915. Efficient searchlights and QF batteries had become even more important with the growing German submarine threat in the western Atlantic. Submarine nets were placed across the harbour; one running from Ives Point to Point Pleasant breakwater. Fort Ives was essential to the protection of this critical line of defence.

With the end of the First World War Fort Ives was closed down and placed in reserve status. During the 1920's training continued to be held at the fort. The only construction, however, was the repair and replacement of existing structures. No new construction was undertaken. When Halifax's defences were analyzed in the 1930's it was found that Fort Ives had become redundant. The decision to move the submarine net seaward to the area between Maugher Beach and York Redoubt confirmed the obsolescence of Fort Ives. The actual closing was delayed, however, because of the time needed to construct new forts further seaward and the rapidly deteriorating political situation in Europe. When war broke out in 1939 Fort Ives was partially operational. The searchlights were used until September of 1940 when the new emplacements at Strawberry Battery became available. While the fort continued to be used as a barracks until 1943 for all intents and purposes Fort Ives' active service in the Halifax Fortress had come to an end.

Fort Ives is the oldest extant fortification on McNabs Island and in several respects its most interesting. Perhaps the most important extant resource at Fort Ives is the RML battery and supporting buildings on the south front. Two of the 10 inch RML's are still mounted on their original carriages and platforms. These emplacements, their shields, ordnance, mountings and supporting buildings are a unique resource within the Halifax Defence Complex. The carriages and mountings are especially important given that they are the earliest surviving examples of this technology to remain in Halifax.Even more significant is the fact that these resources are situated alongside breech loading (BL) emplacements, the next stage in the development of coast artillery. Both BL and Quick Fire (QF) batteries are on the sit. When combined with the searchlight and submarine mining resources the importance of the site is even greater.