- Every Christmas since 1968, the Garden Club of Hamilton has decorated the Castle with fresh fruit and hand-made decorations in period style, and opened the Castle's doors to the public.
- From 1969 to 1970, the Dundurn Repertory Theatre offered children's theatre on the back porch of the Castle, in place of the Sound and Light show.
- Since 1968, the Studio Theatre, Piccadilly Circus, Dr. Bandoli's Travelling Good-Time Show, and many other theatrical and musical groups have played children's theatre and held starlight concerts at the Cockpit Theatre.
- In November 1981, the play "Tamara" by John Krisanc was enacted throughout the many rooms of the Castle.
- From July 1968 to August 1971, and from 1979 to 1980, bagpipe players walked and played in the park during the open hours of the Castle.
- From 1976 to 1978, courses in Victorian decorative arts and cooking were offered to full-time and continuing education students as part of the Canadiana Program at Mohawk College.
- In March 1982, a 12-week course in house restoration was offered to owners of historic homes.
- In April 1994, a contest was held with Sheraton Hotels called "Hidden in History". Contestants had to visit Dundurn Castle to look for a particular historical item, write down what it was, and where it was located. The winner received a free weekend at Sheraton Hotel for the whole family.
- From July 3, 1968, the MacNab Arms Restaurant served meals from two Victorian dining rooms in the Castle, and on the red brick terrace overlooking the kitchen garden. The restaurant closed and reopened several times during the 1980's, and is being reopened in the Coach House in autumn 1996.
- On June 23, 1968, a gift shop was opened in a wing of the Coach House, offering only Canadian products for sale. Today it also holds a large collection of Victorian and Regency craft books and kits.