Fort Dearborn
Located in Rye New Hampshire the first military installations were built during WW1 which included a fire control station 1917 and searchlights 1920. The breakwater seen today was built in 1902. Fort Dearborn was built as a WW2 fortification for the Harbor Defenses of Portsmouth. No other existing Endicott fort could meet the new defense needs (Fort Foster had room for one battery). So it was decided in 1942 that the land between Odiornes Point and Frost Point would become the newest addition to Portsmouth defenses. In order to get this land they would need to remove the current residents and dwellings. So in 1942 the residents were given thirty days to pack their belongings and go elsewhere giving the government the first 200 acres of the reservation in 1943 (The second parcel was acquired later that year bringing the property to about 264 acres). The reservation was officially named Fort Dearborn in 1943 for Henry Dearborn. During this time the coastal highway would be closed for the fort and did not reopen until the 1950s. The first battery of four 155mm guns was built in 1942 while the others were under construction. All WW2 Post structures were demolished after the war aside from the TNT Building and a coupls remaining summer houses.
Battery 155 Odiorne Point
Built in 1942 as a temporary battery of 155mm guns it was only used for the initial construction of the main batteries. Four magazines and a battery commanders station were built behind the emplacements and removed when the main batteries were finished in 1944. Today all that remains is the panama mounts for the guns although one is buried in brush and not visible.
Battery 204
Construction started in 1942 on this six inch battery located at Odiornes Point behind the 155mm battery. Two shielded barbette guns were located on either side of a magazine structure covered with earth. The battery was completed in 1944 and had a battery commanders station built on top and accessed via a ladder from the magazines. The proposed name for this battery was to be Battery M. H. Barry but it was not formally named. Around the structure were various Anti Aircraft guns and Machine Guns.
Battery 103/Seamen
Construction on this casemented 16 inch battery began in 1942 and was completed by 1944. It is located at Frost Point and was the largest guns to defend Portsmouth. The battery construction number was 103 but it was renamed to honor Colonel Claudius M. Seamen. The 25 mile range of the guns meant that Fire Control Towers needed to be used. They were located all the way from Halibut Point Massachusetts to Great Hill in Maine. Similar to Battery 204 the Battery commanders station was built atop the battery and was a side by side station for the Gun Group G1. A concrete Gun Group 1 building is located behind the battery. Due to the shock from the firing of these guns larger caliber batteries like this one were designed to have the plotting room a separate reinforced concrete casement covered with earth. Like battery 204 Anti Aircraft and Machine guns were located around the battery. Shields were added to the guns in 1946.