Luss Parish Church (also known as St Mackessog's)

Luss Parish Church, also known as St Mackessog's, was built in 1875. It is a Gothic church with a T-plan and apsed east end, constructed of squared and snecked pink sandstone rubble with honey-coloured sandstone margins and dressings. The building features plate tracery, a base course, hoodmoulds, and eaves moulding.

The north elevation, which serves as the entrance, has a narrow gabled bay advanced at the centre with a 3-light trefoil-headed window at ground level and a rose window above with hoodmould. A cruciform metal tie sits above. A quatrefoil window at the upper stage appears on the left return, with a classical wall memorial at ground level. A lower octagonal tower stands in the re-entrant angle to the right, featuring a shouldered-arch door with flanking shouldered-arch windows. An ashlar frieze above is pierced with quatrefoil lights. A narrow pointed-arch window sits to the right, with a gabled bay recessed to the outer right. An apsed bay is recessed to the outer left with a window at the centre. A MacFarlane stone Memento Mori panel at the upper stages to the outer left is inscribed "IM 1612" with the text "After death remains virtue" and is part of the fabric of an earlier building.

The east elevation features a canted apse with three 2-light trefoil-headed windows, each with hoodmoulds.

The south (rear) elevation has a gabled bay slightly advanced at the centre with two plate-tracery windows at ground level. A red sandstone plaque at the centre is inscribed to James Duncan and James Robertson with the text "removed from before the altar and relettered by order of Sir James Colquhoun, 1876", with a Latin plaque above. A quatrefoil rose window sits above with a cruciform metal tie in the gablehead. Flanking symmetrical outer bays contain 2-light windows.

The west elevation has a gabled porch at the centre ground with a 3-light pointed-arch window at the centre. An inscribed marble plaque in the gablehead reads "rebuilt by Sir James Colquhoun" with a psalm. A 3-centre arched door to the left return is boarded with a decorative bracket, with a window to the right return. A rose window sits at the centre.

The roof is slate grey with lead flashings, ashlar coping to the skews, trefoil finials, and gabletted skews. Stained glass windows are present throughout.

Interior features include a porch with floral stained glass presented by the Kirk Session in 1892. A decorative open wooden roof is supported on stone corbels and arched braces. A simple altar table sits in a slight recess against the south wall. A gallery and heritors loft occupies a recess in the north wall, with the lower area now used as a church shop. Stained glass windows include one inscribed "feed my lambs, feed my sheep" in memory of John Page Readle of Crowe Hall, Suffolk, who died in 1852. The head of St Kessog appears in the apse. The Colquhouns are keepers of the Bachuil of St Kessog.

Two lych gates, broad and low with jerkin-headed timber construction, stand to the north and west. They feature stugged sandstone bases with paired carved consoles supporting gables over pointed arches. The gates are inscribed on their outer faces "Let us go into the house of the Lord Psalm CXXII I" and on their inner faces "Now is Christ risen I Corinth XV 20". The gates themselves are timber and cast iron panelled.

The boundary wall is constructed of stepped whinstone rubble with harl-pointing in a battlement arrangement and rusticated slab coping. Cast iron railings infill the battlements, featuring arrowhead and quatrefoil designs. Steps with a solid whinstone balustrade lead to the graveyard along the north wall.

A number of 19th-century grave memorials are present within the graveyard.