Event/Activity EPM285 - Archaeological Watching Brief Southsea Castle GI Works

Wessex Archaeology carried out archaeological monitoring on Geotechnical Works located within or adjacent to the boundary of the Scheduled Monument of Southsea Castle in July and September 2020. The work was commissioned by the Eastern Solent Coastal Partnership as part of the larger Southsea Coastal Defence Scheme. A total of 13 trial pits and four rotary core boreholes were monitored during the watching brief which took place between the 13th and 16th July and the 21st and 22nd September 2020. Scheduled Monument Consent was granted for the work. The investigations encountered the remains of a 19th century promenade and provided information relating to the outer construction of the counterscarp tunnels at Southsea Castle that formed part of extensive alterations made between 1813 and 1816. A Ground Penetrating Radar (GPR) survey was also conducted as part of the works with the aims of establishing the extent of stone paving beneath the modern surface, locating the counterscarp tunnels and to test whether voids within the sea defence revetment could be identified. The survey identified areas to the south-east and south-west of the castle that were thought to be associated with the 19th century promenade. Only limited information regarding the extent of the tunnel was obtained as it was not possible to clearly distinguish the masonry that formed the outer structure of the tunnel from redeposited storm beach deposits.