By Daniel Dickinson In Zanzibar

The 1964 revolution came shortly after the island archipelago gained independence from Britain.Zanzibar is now part of Tanzania.

Zanzibar President Amani Abeid Karume praised the material benefits gained in the past four decades but lamented the impact of Aids on the island. Tribute was paid to the thousands of people who died during the revolution.

Anniversary celebrations culminated in a Revolution Day rally at Zanzibar's national stadium.

Today Zanzibar bears few marks of its violent revolution

On 12 January 1964 the people of Zanzibar rose up against what they saw as a government toeing the line of the recently departed British colonial administration.

It was swift and bloody with up to 17,000 deaths. Zanzibar was left to decide its own political future.

Forty years on, Tanzania's ruling Chama cha Mapinduzi party (CCM), is celebrating a huge improvement in people's lives - fresh water, new schools, better roads and jobs created by tourism, the island's most important industry.

CCM Deputy Secretary General Saleh Rahmadan Feruzi told BBC News Online that they have been building on the successes of the revolution.

"There were big changes in the early days... But the biggest change was that for the first time we had freedom of movement and freedom of expression. That legacy lives on."

The opposition Civic United Front (CUF) is not so happy. It accuses the government of mishandling the economy.

Flashpoint

The average wage of Zanzibaris is around 60 US cents a day.

The CUF also says political oppression is still rife. At least 30 CUF supporters were killed in 2001 following protests over elections that were allegedly rigged.

"Although there has been some improvement, the freedom of individuals to express themselves is still limited," said CUF's director of foreign relations, Ali Pandu told BBC News Online.

"People who speak out against the government often find it difficult to get promotions at work."

Tourism is the island's main source of cash

The international community will be closely monitoring the next potential flashpoint - elections due in 2005 - to ensure they are free and fair.

If the CCM wins, it is expected Zanzibar will retain its strong political links with mainland Tanzania.