The village stands on uneven ground, sloping from south to north, at the foot of the southern outliers of the Cheviot Hills.

A rare bronze spearhead has been found at High Bleakhope to the north-west of Alnham, possibly indicating occupation by an elite social class.

Remains of hut circles within the inner closure suggest that Castle Hill was a settlement with a small population.

[9] During the Middle Ages Alnham was an important location, as indicated by its ancient buildings, castle mound, and pele tower.

The Church of St Michaels was first recorded in an 1184 charter in which William de Vesci granted Alnham and its tithes to Alnwick Abbey.

In 1293 William de Vesci claimed free Chase in Alnham, but with no male heirs, his property was passed to Antony Bek (Bishop of Durham) after his death.

[11][12] The history of Alnham was often troubled, including by climatic deterioration and harvest failure in the early 14th century, and the Black Death.

[14] The surviving residents of Alnham, however, may have benefitted somewhat from this reduction in population and secured better rights: the Inquisition for Henry de Percy in 1368 reveals that the bondages and cottages were held by "tenants-at-will", in comparison to earlier non-contractual tenancies which owed labour services to a lord.

[15] Being situated in a precarious position between the English and Scottish borders, Anglo-Scottish combat also caused disruption in Alnham.

Two letters from the Earl of Northumberland to the King, dating from October and November 1532, describe how the Scots came across the borders and rampaged Alnham and surrounding towns.

[16] The tower at Alnham appears to have suffered damage from the Scottish raids as it was reported to have been in a bad condition by 1541.

[18][21] The grounds were divided up into holdings along the east and southeast sides of the township and a new road was built through the village.

Further divisions of the land were granted to Alexander Collingwood, Charles Byrne, Percival Clennel, and the Vicar of Alnham.

[26] The 1831 census revealed that the majority of male residents aged over 20 in Alnham Parish was labourers or servants (45 men).

In the Medieval period, Alnham formed one of the manors of the Barony of Alnwick held by the Vesci lineage beginning in the early 12th century and ending in 1310.

[32] In local government, Alnham is part of the Rothbury Ward and is represented by Steven Christopher Bridgett (Independent).

[35] The Church of St Michael and All Angels is a Grade I listed building and part of the Diocese of Newcastle.

[10] After William de Vesci gave the Church to Alnwick Abbey, a new west front, south chapel, north aisle, and chancel arch were constructed.

The eye is met by a green flash from the damp, mildewed walls, and by streaks of sky seen through the unceiled slates.

The western end, with its Early Traditional single light, has not been much disturbed; but the rest of the window opening have been modernized and filled with common sashes, which are rotten, and let in wind and rain.

The east end has a small square sash, such as is ordinarily provided for a scullery or any inferior office.

Three of the worm-eaten, mousy pews are square, with a table fixed in the centre of each: a fourth forms three sides of a quadrangle that is occupied by a stove.

It is a large stone, 2 feet (61 cm) high, with a socket cut into it to hold the shaft of a cross.

[41] The Medieval settlement at Alnham is a scheduled monument and is located to the south of St Michaels Church.

This enclosure most likely consisted of a garden and meadow associated with the manor as recorded in the Inquisition of Henry de Percy in 1368.

[46] The garden wall attached to the front of the Pennywells, also built out of roughly-dressed stone, is another Grade II listed structure.

[47] There are adjacent farm buildings, around 9 metres (10 yd) from the Pennywells, consisting of byres, a stable and shelter sheds which were built around a courtyard between around 1830 and 1840.

[49] It consists of a sub-circular enclosure within concentric ditches with ramparts which are built from earth and stone excavated from the site of the hillfort.

[50] Three unenclosed huts on the north-west flanks of the hillfort, defined by a curving out bank, constitute the earliest of the remains, possibly dating from the Bronze Age.

There is evidence that Medieval cultivation stretched from Alnham village and stopped at a boundary bank to the south-east face of the hill.