1805 – Grand Hotel, Shannon Harbour, Co. Offaly Architect: David Henry Completed in 1806, the Grand Hotel was one of a series of hotels for travellers on the Grand Canal.
1806 – Dhuarigle Castle, Millstreet, Co. Cork Dhuarigle Castle was a fine Gothic Revival castellated house, built 1806 by Thomas Justice, incorporating the remains of a medieval tower house to the west.
1806 – Former Court House, Wexford, Co. Wexford Architect: Richard Morrison The old Wexford Court House was situated on Wexford’s Commercial Quay, directly across from the town-side entrance of Wexford Bridge.
1806 – Killakee House, Rathfarnham, Co. Dublin A 36-room, two-storey, symmetrical, stucco-faced house of with several curved bows. It had a balustraded parapet to the roof, a veranda with slender iron uprights and a balcony above along the centre of the front.
1806 – Shanbally Castle, Clogheen, Co. Tipperary Architect: John Nash Shanbally Castle was built for Cornelius O’Callaghan, the first Viscount Lismore and was the largest house built in Ireland by the noted English architect John Nash.
1806 – St Elisabeth Kirche, Nuremberg, Bavaria A small classical church with large drum and dome, formerly the private chapel of the Teutonic Order Hospice. The building may have been better looking if the drum had been centrally sited.
1806 – Trinity College Botanic Gardens, Ballsbridge, Dublin In 1806, Trinity College took a lease on two acres of land at Ballsbridge, later extending it to a total of just over seven acres by 1848.