Situated adjacent to Lyndon Hall in an idyllic churchyard, the small church of St. Martin found its full form in the late 13^th/early 14^th c. based on the existing two bays of the nave arcade and the chancel arch. The plain S doorway with its pointed arch and single order is of the early 13^th c. though the S porch itself is new, likely of late 19^th/early 20^th c. date. The chancel, nave and W tower were extensively rebuilt in 1865-66 by T. G. Jackson. Of the Romanesque period there is the font and a loose fragment of a cross-head.

Lyndon is not mentioned in Domesday Book, however it is believed to be one of the seven berewicks dependent on the manor of Hambleton which belonged to Queen Edith in 1066. William the Conqueror granted Lyndon manor to the first earl of Warwick whose line maintained possession of it until the 15^th c. Though the church is first mentioned in 1315, the font and cross-head fragment are evidence of the presence of a church at this location in the 12^th c.

According to VCH: Rutland, v. II, the font was found buried in the churchyard in 1866, the same year in which Jackson was undertaking a major restoration of the church. The church guide inside the church states the font was found in the churchyard in 1865. Some descriptions of the font, such as Mayhew’s, describe part of the ornament as a “rudely carved animal” but no details on the font support this interpretation. The undulating ornamental design on this font, and the unusual abstract treatment of the upper corners, is strikingly similar to that found on the font at St. Peter and St. Paul in Market Overton, Rutland. Are they from the same workshop? The legs of the font are likely from the 19^th c. and created after the discovery of the font in the churchyard; their ambiguous design appears to be a reflection of the undulating ornament of the bowl.

It is believed the cross fragment was originally part of the village cross. A letter in the church dated January 1904 states that “during the demolition of part of a house occupied by Mr. J. Foster the top part of a cross was discovered which had been built up in the wall. This was probably part of the village cross, which is shown in a map of Lyndon, dated 1663, in possession of E.W.P. Conant, Esq. The cross stood where the well now is at the junction of the four roads in the village.” Mayhew notes another account which claims the cross fragment was part of a finial cross and dates c. 1130.