Eight years later the "Sem" opened its doors to its first students, and for over a century-and-a-half the school has adapted itself to meet the educational needs of boys in the North Monaghan and surrounding areas.

The building has a chapel, a collection of antiquities and a clock tower and includes a large lunch canteen, which was formerly used as a refectory for the school's boarders.

[citation needed] The crest of St. Macartan's College, as seen in the front hall of the school, was designed by the artist Richard J.

The panels contain the interlaced letters DEUS (God), and, underneath, the motto of the college, Fortis et Fidelis.

[citation needed] The words "Fortis et Fidelis" (Strong and Faithful) suggest a Pauline quotation from 1 Cor 16:13.

They evoke the legend of St. Mac Cairthinn, the tréanfhear of Patrick, the bodyguard and champion of the Saint who used to carry him across fords and rivers on his missionary journeys.

The words occur in one of the last letters of Father Cornelius Tierney, a former student and priest-teacher in St. Macartan's, and later a Columban missionary who died a prisoner of Communist guerillas in China in 1931.

St. Macartan's won the Senior Ulster Colleges MacLarnon Cup on 17 March 1987, beating Armagh C.B.S.