The village includes public parkland with footpaths and abuts the River Colne and biodiverse land in its Regional Park to the west, once the grazing meadows and woodlands used for hogs of Colnbrook.

The west of the parish has two major airline headquarters (international and local) and two immigration detention centres: the larger is for a maximum of 620 men without leave (permission) to enter or remain in the United Kingdom.

Many international visitors stay within the church-based bounds of Harmondsworth, as all hotels are branded as "Heathrow", a former hamlet and other farmsteads that were absorbed by the airport.

According to current expansion plans, around half of the existing village of Harmondsworth will have to be demolished to make way for the north-west runway and surrounding grass safety area.

[2] Harmondsworth remains an ecclesiastical parish, with the name first recorded in AD 780 when King Offa granted land to his servant Aeldred.

In 1069 it was granted by the king, on the suggestion of William FitzOsbern, 1st Earl of Hereford (c. 1020 – 1071),[4] to the Benedictine Abbey of Holy Trinity, Rouen, afterwards known as St. Catherine's, which held it in 1086 and then until 1391.

[note 1][5] HARMONDSWORTH (Virgin Mary), a parish, in the union of Staines...Middlesex, 2½ miles (E. by N.) from Colnbrook; containing 1330 inhabitants.

The living is a vicarage, with that of West Drayton united, net income, £530; patron, H. De Burgh, Esq...The church has a Norman door, and a tower with angular turrets, On Hounslow heath, in the parish, is a square intrenchment, each side measuring 100 yards, supposed to have been the work of Caesar in his war with Cassivelaunus.

A brick-works was established by the corner of Cain's Lane and Heathrow Road and the area of former heathland was extensively worked for gravel, sand, and grit.

In the 1930s Middlesex County Council opened a large sewage pumping station to the west of Perry Oaks, which was converted to Heathrow Terminal 5 in the early 21st century.

It was then suggested that further expansion in the Yiewsley and West Drayton area should be curtailed, as the land was primarily in demand for agriculture, which was greatly adhered to until 1971.

This entailed the complete demolition of Heathrow and Perry Oaks hamlets, and widespread draining of the old flooded gravel pits.

[14] Record of proceedings in the Church of Pinnore [Pinner], before the Dean of Middlesex, and Baldric, Chaplain acting on behalf of the Priors of Benetleye [Bentley] and Hermodesworth [Harmondsworth], in the cause between the Abbot and Convent of Bec, by Peter de Suynecumbe, Proctor, and John de Bleddel also Proctor for the Abbey of Bec [ Bec Herluin ] and the Rector of the Church of Great Wrothing [Great Wratting] by Master Henry de Trippeleawe his Proctor, and the Prior and Convent of Doure [Dover].

[28] The Bishop sent a member of his household, Richard Altryncham, to Rouen to negotiate with the abbey and convent about this buying of the priory as an endowment for his colleges.

The bishop also undertook to provide for the prior Robert Beauchamp and for John le Cellier, his companion, all such things in the way of wine, food, clothing, and lodging as befitted religious of their estate for the rest of their lives.

[29] The Harmondsworth property, centered on the priory which stood to the west of Manor Farm and the tithe barn, thus became part of the endowment of his two colleges at Winchester and Oxford.