It was built by the 1st Earl O'Neill as a hunting-lodge.
The estate comprised 160 acres.
It had a five-bay front with three-sided end bows; a three-bay projecting porch with a Wyatt window in the centre.
The roof was eaved and the chimneys were grouped together in a long stack.
It was said to be built of cut stone, plain, though handsome; situated in the midst of the demesne, well ornamented by elms and oak trees, some of which attained a considerable size.
The Lodge had "some good paintings", and the gardens being well laid out and extensive.
It was initially inhabited by the Hon John Bruce Richard O'Neill MP, younger brother of the 1st Earl:
JOHN BRUCE RICHARD (1780-1855), 3rd Viscount O'Neill:
In 1802, O'Neill was elected MP for Antrim. He held the seat until 1841, when he inherited the viscountcy from his brother Charles, 1st and last Earl O'Neill. The 3rd Viscount died in 1855, when his titles became extinct. He was succeeded by his 2nd cousin twice removed, the Rev William Chichester, prebend of Christ Church, Dublin, who changed his name to O’Neill and was created Baron O’Neill [UK] in 1868.Tullymore passed to the Hon Edward O'Neill (1839-1928), later 2nd Baron O'Neill.
Thereafter the Lodge became the home of the 2nd Baron's sister, the Hon Anne O'Neill (1848-1934), only daughter of the 1st Baron O'Neill, who moved there ca 1883 with her brother, Major the Hon Robert Torrens O'Neill.
First published in November, 2013. I am indebted to Henry Skeath, without whose assistance this article might not have materialized.