Michelmersh is in W central Hampshire, three miles N of Romsey. The substantial village stands on high ground overlooking the river Test, which flows from NW to SE a mile to the SW. The land around is mostly pasture and well wooded, with Michelmersh Wood immediately N of the village. The church is at the village’s northern edge.
St Mary’s has a nave with a S aisle, sharing a single roof, and a S porch, a chancel with a N chapel, and a weatherboarded tower at the W end of the aisle. Nave and chancel are of knapped flint; the S nave aisle wall being very low, so that the porch roof overlaps the big roof over the nave and aisle. The nave is 12thc with plain doorways of that date at W and S; the latter covered by a 19thc flint and timber porch. The N nave windows are big three-light 15thc openings. The chancel must be 12thc too, as it had 12thc chapels to N and S. Both chapel arches remain, but the S chapel has been removed, the arch blocked and a three-light window inserted. A resistivity survey in 1998 suggested confirmed the presence of a chapel. The N chapel has been rebuilt larger, with a roof running E to W. It now serves as a vestry and the organ fills its arch. The chancel itself has been lengthened; the quoins of the original E angle remaining on the S wall. To judge from the fenestration this took place in the mid-13thc. The S nave aisle was rebuilt in an extensive restoration of 1846-47 by W. Gover of Winchester, and the striking S elevation of the nave is entirely Gover’s work. The church was again restored in 1888 under the supervision of Arthur Blomfield, who was extremely critical of Gover’s restoration which, he said, had destroyed “whatever beauty of detail it may have possessed many years since.” In particular, Gover’s rebuilding removed any evidence that might have elucidated the relation of the church to its weatherboarded tower. This was built as a free-standing structure, like the similar tower at Perivale (Middlesex), and is characteristic of the years around 1600. There is evidence of repairs to it in 1846 and 1897. The only Romanesque features are the chapel arches and the W and S doorways.