Lilley is a village in North Hertfordshire, set in rolling farmland less than a mile from the Bedfordshire border. It is 3 miles NE of Luton (Beds) and 4 miles SW of Hitchin, on the N side of the A505. The village has a long high street running N-S with the church towards its southern end.

St Peter’s was rebuilt in 1870-72 in an Early English style by Thomas Jekyll, incorporating earlier material in the 13thc piscina, the 15thc font, some stones of similar date in the S doorway, and the 12thc chancel arch, reused as the arch for the organ chamber on the N side of the chancel and described below. Jekyll’s church is of uncoursed flint with ashlar dressings, and consists of a chancel with with a N vestry and organ chamber, and the tall Sowerby chapel on the S, approached by stairs from the SE corner of the nave. This is unaisled and has a tower porch at the SW corner. The tower itself has a parapet of chequerwork in stone and tile.

Lilley was held by Leodgifu from Earl Harold in 1066, and in 1086 the manor, assessed at 5 hides, was held by Geoffrey de Bec. 2 hides were in demesne, and the rest was held from him. The recorded population of 19 villans, 6 bordars, 4 cottars, 6 slaves and a priest suggests a total population of some 200 people, making Lilley a substantial settlement.

By the early 13thc the manor was in the tenure of William Malet of Gerardville, but in 1204 it was granted by King John to Matthew de Lilley.

Oughtonhead Lane, 4 miles to the NE on the edge of Hitchin, is a geological SSI by reason of the Hoxnian interglacial tufa found there. This may be the source of the stone.