Ms Robinson lauded the contribution of the Northern Ireland political process which ended violence in 1994 and said without it “today would not have happened”.
She was invited to Cambridge to accept an honorary degree in 1991 and two years later had tea with the queen in an unprecedented diplomatic breakthrough.
The former UN human rights high commissioner said yesterday was a good day for relations between Britain and Ireland and praised the work of her successor President Mary McAleese.
“It is wonderful that now it is coming to fruition for both islands,” she said.
Ms Robinson acknowledged security concerns and said it would have been good if the queen could have met more of the public. She guided the queen around Trinity College as chancellor of the historic institution.
“Security has to be taken seriously and there were sufficient indications that there might be a problem. For the relations between our two countries this is a very good visit,” she said.
Ms Robinson said the royal event needed the peace process.
“We could not have had a visit like this without the peace process,” she added.
She said the protests had not spoiled the visit and the queen and Duke of Edinburgh had thoroughly enjoyed themselves.
For more than 400 years Trinity has produced some of the world’s greatest minds, including two nobel laureates, Samuel Beckett in literature and Ernest Walton in science.
The queen viewed the priceless ninth century Latin gospel copy — the Book of Kells — as well as the Royal Charter of Queen Elizabeth I for Trinity College Dublin, signed in 1592.
Provost of the university Dr John Hegarty guided her round and said the queen wanted to know was the Book of Kells still being studied, which it is.
The marble bust of Jonathan Swift, whose satire helped define Irish literature, looked over the queen as she made her way down the 65m Long Room, lined with 200,000 of the library’s oldest books from floor to ceiling and deeply symbolic of the learning of the institution. Depictions of many of the great philosophers and writers of the western world adorn the walls of the room.
The ranks of people assembled to meet her in the atmospheric library burst into applause as she entered and at least one person bowed as he greeted her.
The queen lingered listening to a recital of Ireland’s oldest harp.
Dating from the 15th century, legend has it that it belonged to Brian Boru, who died the Battle of Clontarf in 1014.
Dr Hegarty added: “She was intrigued by the sound of the harp, she was listening to it and saying it was a very unusual sound.”
Among those who met her in the Long Room were renowned composer Micheál Ó Súilleabháin.
The royal couple were accompanied by British Foreign Secretary William Hague, Education Minister Ruairi Quinn and minister of state for training and skills Ciaran Cannon.
Poet Nuala Ní Dhomhnaill also met the queen and told her she was a poet in the Irish language.
“She had very intelligent eyes,” she said.