The Bronze Age starts around 2300 to 2200 BC in Britain. It is the period when metal-working and, in particular, bronze working, becomes widespread. Some metalworking, often of gold or silver, took place in the Neolithic but the smelting of copper and creating an alloy with tin was a more advanced step. At first, in the Early Bronze Age, bronze was used for a limited range of weapons and ornaments, and flint was stil used for many tools, but later in the Bronze Age it becomes more commonplace and is used for a wide range of tools as well. The Bronze Age is usually split into Early (c. 2300-1600 BC), Middle (1600-1000 BC) and Late (1000-700 BC).
The Early Bronze Age is quite similar to the Late Neolithic and there are often flint scatters that cannot be dated securely to either period. The most recognisable Early Bronze Age sites are round barrows. These are circular mounds of earth surrounded by a ditch and usually covering an individual burial or cremation in a pit. Later burials, Bronze Age, Roman or Saxon, were often made in the mound, ditch or next to the barrow. Some of the more famous groups of round barrows are in Wiltshire close to Stonehenge. There are a few surviving round barrows in Buckinghamshire at Ivinghoe Beacon, Lodge Hill in Saunderton and in other places. many have not been excavated and so it is possible that they actually date to different periods. Where barrows have been ploughed flat, the mound disappears and only the ditch is left. This can usually be seen as a dark circle on aerial photographs, where the fill of the ditch is darker than the surrounding soil. These ring-ditches, as they are known, are very common in river valleys as they show up better on soil which is underlain with gravel. Many have been identified along the Thames, for instance at Dorney, and the Great Ouse in the north of the county at Leckhampstead, for instance.
A series of Early Bronze Age (although one may date to the Late Neolithic) burnt mounds were excavated at Little Marlow on either bank of a stream tributary of the Thames. Burnt mounds are spreads of flint that has been heated in fires and then put in water to heat it, possibly to cook food. The sudden change in temperature causes the flint to change colour and craze. The spreads of crazed flint tend to be associated with troughs that were possibly for holding the water that was heated. One of the Early Bronze Age burnt mounds at Little Marlow didn't have a trough but was right next to a stream channel. There were a number of post-holes that may have been to support an awning over the edge of the stream and a couple of large, unburnt stones could have weighted down the awning material. The excavators thought the awning could have been a sweat lodge and the flints were used to create steam.
Early Bronze Age settlement often takes the form of flint scatters, but has also been found as a series of pits at Walton Lodge Lane. Later in the Middle Bronze Age there is a more extensive settlement that has been found at a number of excavations in Walton, just south of Aylesbury. The circular gullies that were excavated would have been to help drain the round-houses and there are several post-holes from the houses and pits that would have been used to put rubbish in or possible store grain.
Middle Bronze Age people were usually cremated and burial was in flat graves, grouped together in cemeteries. A cemetery like this has been found south-west of Dorney Church and there are also flat cremation graves nearby at Lake End Road West and one found in the excavations for Eton Rowing Lake. The area seems to have been important because of the proximity of the River Thames. Several Middle to Late Bronze Age and Iron Age timber bridges and jetties have been found in nearby excavations in silted up former channels of the Thames. These bridges may have been practical walkways for getting to and from islands in the river, but were also probably used to deposit artefacts into the river channel in ceremonies.
Bronze tools and weapons seem to have been placed in rivers, particularly into the Thames (though this might reflect the regular dredging of the Thames rather than a real concentration) for ritual purposes, perhaps to stop the rivers flooding or to 'kill' a particular artefact after its owner had died. Many Bronze Age artefacts have been found in the Thames, including an Early to Middle Bronze Age dagger and Middle Bronze Age rapiers at Bourne End, an Early Bronze Age flat axe-head near Bray ferry at Taplow and a Late Bronze Age sword near the Queen's Eyot, Dorney. A Middle Bronze Age spear-head was found in the bank of the River Misbourne at Amersham. Some artefacts may have been eroded out from river-side settlements, rather than placed straight into the river.
Some of the hillforts in Buckinghamshire were first constructed in the Late Bronze Age. Taplow hillfort, recently discovered in the grounds of Taplow Court, also has its beginnings in the Late Bronze Age and was also occupied in the following Iron Age. In fact, there were three phases of development. The first Late Bronze Age phase was a site defended by a wooden palisade. Later a large V-shaped ditch was dug in the very Late Bronze Age and then after that a U-shaped ditch in the Iron Age. Other settlement sites have beene excavated, including one at the Former Nurses Home, Stone. There were a few post-holes, pits and ditches over a wide area.
The landscape starts to be divided up in the Late Bronze Age. Large cross-ridge dykes, linear banks with a ditch on one or both sides, carved up the landscape probably into territories. It is thought that animal husbandry was still very important in the Late Bronze Age and these dykes were used to mark out the area that one group used for their herds. Animals needed to be moved around so that they did not exhaust the land they were grazing and it is likely that there were summer and winter pastures. These dykes, then, enclose very wide areas. They can be seen on Ragpit Hill and Whiteleaf Hill. It is possible that sections of Grim's Ditch also date to the Late Bronze Age.
The Bronze Age comes to an end when iron is discovered. Iron-working takes a lot more effort but the ore is found everywhere, whereas the ore for copper is quite rare. The Iron Age sees the construction of hillforts in particular, of which there are many in Buckinghamshire.