Archaeological strip, map and excavation, as well as monitoring during all topsoil stripping, was carried out by Oxford Archaeology East during the construction of a 10km pipeline (10-15m wide) between Great Horkesley (W) and Ardleigh (E). Eight fields (c.2.2km in total x c.6-7m wide) were selected for strip, map and excavation and/or monitored (excluding that part of the route in Tendring): C2, C5, C6, C10, C11, C12, C13 and C14.<1> Two archaeological sites were defined along this length of the route, Site 1 (South of Boxted Road, Great Horkesley, fields C12 - C14) and Site 2, South of Park Lane, Langham (field C2). In Site 1, field C14 produced four ditches and two pits/postholes, C13 produced four ditches and six discrete features (including pits with charcoal-rich fills) and C12 produced three linear features. One pit (1078 in field C13) produced 348g of pottery and an environmental sample produced charcoal and iron working slag. In addition, two medieval sherds found unstratified in Field C12 are probably kiln wasters. Five linear features and eight discrete features (pits and postholes) were defined in field C2 (Site 2); one pit (1015) produced 22 sherds of Late Iron Age/early Roman pottery. Small pieces of slag were also noted in the fill of gully 1017 (field C2). One pit (1001), containing a charcoal-rich fill, was RC dated as modern. In addition, monitoring of fields C5, C6 and C11 (South of Old House Lane) produced 12 pits with charcoal rich fills. The fill of one of these pits (1054) was RC dated to 21 BC - 125 AD (92.8% probability).