the disadvantages of Chatham (and also of the Thames-side yards) was their relative inaccessibility for ships at sea (including those anchored in The Nore). Therefore, rather than risk being constrained by wind, tide and draught on a journey upriver, ships would seek as often as possible to do running repairs and maintenance while at anchor, and would only travel to the dockyard when necessary. Thus deliveries of victuals, ordnance and other supplies were made by small boats, sailing regularly between Chatham and The Nore. Seeking to alleviate this less-than-satisfactory situation, the Navy Board explored options for developing a shore facility with direct access from the open water of the Thames Estuary. The escalating Anglo-Dutch wars forced their hand, however: several temporary buildings were hastily erected in Sheerness, at the mouth of the Medway, to enable ships to re-arm, re-victual and (if necessary) be repaired as quickly as possible. In 1665, the Navy Board approved Sheerness as a site for a new dockyard, and building work began; but in 1667 the still-incomplete Sheerness Dockyard was captured by the Dutch Navy and used as the base for an attack on the English fleet at anchor in the Medway itself. Sheerness remained operational as a royal dockyard until 1959, but it was never considered a major shore establishment and in several respects it operated as a subsidiary yard to Chatham. Consolidation By the late 17th century a number of prestigious new buildings were erected (including the officers' residences, the clocktower storehouse and the main gatehouse), several of which are still in place. At the same time, the nearby village of Brompton began to be developed to provide housing for the dockyard's growing workforce. From the very start of the 18th century, however, Chatham began to be superseded in both size and importance, first by Portsmouth, then Plymouth, when the main naval enemy became France, and the Western approaches the chief theatre of operations. In addition, the Medway had begun to silt up, making navigation more difficult (especially as the Navy's ships were getting larger). As a result, it was acknowledged by 1771 that Chatham had no future as a front-line fleet base; nevertheless, following a visit by the Admiralty Board in 1773, the decision was taken to invest further in Chatham, and to develop it as a building yard rather than a refitting base. By this time the establishment, including the gun wharf,