The book's first pages were filled within half an hour of its opening

The book honouring Lord Callaghan. who died on Saturday, was opened at midday on Wednesday.

Officials in Cardiff said they were responding to the overwhelming outpouring of grief from people across Wales

James Callaghan was an MP in Cardiff for 42 years.

"Lord Callaghan was a significant figure in both Cardiff politics and UK politics," said Cardiff Council leader Rodney Berman

"(He) represented a constituency in Cardiff for over four decades, that's quite a remarkable achievement in itself.

Brigid Bingham came because Lord Callaghan helped her mother

"I'm sure there will be people who will remember him quite fondly from those years and will want to come along and express that."

One of the first people to sign the book was Brigid Bingham from Cardiff.

She said: "He helped my mum and mother-in-law years ago and he kept in contact every year at Christmas with them. That's really why I came, for their sakes.

"He was good, down-to-earth, someone you could talk to."

Welsh Secretary Peter Hain called him a "much-loved adopted son of Wales" and assembly First Minister Rhodri Morgan said he made an "immense contribution".

Lord Kinnock, one of his successors as Labour leader, applauded his "justice, great dignity and determination".

Lord Callaghan died at his home in East Sussex, a day before his 93rd birthday and only 11 days after the death of his wife of 67 years, Audrey, who was 91.

He was prime minister from 1976 to 1979, and became the first of three successive Labour leaders to represent south Wales seats. He was followed by Michael Foot, then MP for Blaenau Gwent, and Neil Kinnock, who represented Islwyn.

He was MP for Cardiff South-East - later Cardiff South and Penarth - from 1945 until his retirement at the 1987 general election.

Neil and Glenys Kinnock who met and cut their political teeth together at Cardiff University in the 1960s, said they had the "great pleasure of working with Jim" when they were students.

"Jim had a strong sense of justice, great dignity and determination, and he will long be remembered with huge affection and respect in Cardiff, Wales and internationally," they said in a joint statement.

Lord Callaghan died 11 days after his wife Audrey

Rhodri Morgan was another young political activist in Cardiff at the time and joined the Labour Party in Lord Callaghan's constituency in the early 1960s.

Mr Morgan, who became MP for neighbouring Cardiff West in 1987, said he had lost "a great friend and mentor".

Roots

"He may be the last British politician to have risen from real poverty to the top of the British political tree but the notable thing with Callaghan was that it would never have occurred to him to have a chip on his shoulder about anything," said Mr Morgan.

Neath MP Mr Hain, who is also leader of the Commons, said: "Jim Callaghan was a much loved adopted son of Wales, who achieved fantastic heights in government. He will be sorely missed."

Alun Michael, who succeeded Lord Callaghan as MP for Cardiff South and Penarth, said he never lost touch with his roots.

"His many friends in the constituency will miss the regular contact he maintained even after he ceased to be our MP.

"His leadership as prime minister in an enormously difficult time for the Labour Party and the tremendous contribution he made nationally and internationally has always been underestimated."

Conservative leader Michael Howard, who was born and raised in Llanelli, south Wales, said: "Lord Callaghan was the only politician to hold all the high offices of state.