Portland Harbour

Portland  was designated as a Class B harbour by the  Home Ports Defence Committee, later the Home Defence Committee and was intended to resist attack from armoured cruisers.

Over the years a number of coastal defenses were built but by 1914 there were four main sites:

• Breakwater Fort was a single tier armoured fort with 14 guns in casemates that was built between 1861 and 1875.  Between 1908 and 1909 two 6-inch Mark VII were mounted on the roof of the old casemates.

• Inner Pier Head Fort for which was a circular fort constructed on the south breakwater between 1859 and 1862 by the Admiralty. It was then taken over by the War Department and between 1897 and 1899 armed with two 12-pdr Q.F. gun mounted on the roof of the original fort.
• A Pier Head
• B Pier Head
• C Pier Head
• East Weare Battery which included a number of earthen positions which mounted Rifle Muzzle Loading guns.  These were designated as Battery A through to E, some five locations. Between 1899 and 1901 the ‘A’ and ‘B’ Batteries (most southernly) were upgraded to mount two 9.2-inch Marks X guns and three 6-inch Mark VII guns respectively.
• Blacknor Battery which was built between 1900 and 1902 and then rearmed between 1905 and 1906.  Armed with two 9.2-inch guns.
• Nothe Fort was a granite fort built between 1860 and 1872 with ten Rifle Muzzle Loading guns in casemates.  Between 1902 and 1904 three 6-inch Mark VII guns were mounted on the roof.
• Verne Citadel on the escarpment above Queens Town.
• Upton Battery

At Queens Town on Portland Island, a harbour had existed from early times but in 1849 work began on creating a Harbour of Refuge here.  Work commenced on two breakwaters on the south side.  The smaller of these was a continuation from Queens Town and ended at Inner Pier Head Battery.  The longer stretch ran out to Breakwater Fort with a small channel South Channel between.  The work on these two breakwaters was completed by 1872, with Breakwater Fort nearing completion on the eastern end of South Breakwater.

By 1893 there was growing concern about the threat to anchored warships in the harbour posed by motor torpedo boats.  In accordance the Colonial Defence Committee instructions of that time, it was proposed to protect the eastern approaches to the harbour with additional breakwaters.  In 1893 the funds were approved for these new breakwaters, but they would take ten years to build.  As an interim measure a temporary boom defence was constructed which consisted of:

A rock bank was laid on the seabed to cover the sea between the fortified posts and boom platforms.

Eleven platform were fixed in place, these were constructed of wood and metal.  Four of the platforms mounted guns, the other seven had equipment for the boom defences.

Each of the armed platforms had a crew of five men and one office. There was accommodation and ammunition storage on the platforms.

Four of the sea forts was originally planned to mount two 6-pdrs but this was upgraded in the following year to 12-pdr QF guns.  They also mounted two Maxim Machine Guns.

Two channels were left through the rock bank to allow the movement of friendly ships.  These point were covered with booms, operated from the platforms.

The boom defences supplement the rock bank as a means of preventing Motor Torpedo Boats entering the anchorage.

The remaining seven pltforms were fitted with winches and equipment for operating the boom defences.

There was also a defence post on Bincleave Pier Head.

Supplementary Motor Torpedo Boat defences around the anchorage were built between 1897 and 1899 and included:

1. Inner Pier Head was upgraded to mount two 12-pdr QF guns and two Maxim Machine Guns.
2. Two 12-pdr QF guns on Breakwater Fort.
3. Defence Electric Lights, with four at Breakwater Fort, two at North Fort and two at Bincleave Point.

The new permanent breakwaters were built roughly along this temporary defence line.  The permanent breakwater was completed in 1903 and costal batteries were built on three of the piers heads, designated A, B and C.

There is an excellent short article by Dunan Williams on these temporary sea forts in The Redan, issue Number 83 of 2022 which is available from the Palmerston Forts Society.