Aside from the intense heat rising off the tarmac, what struck me most as I set foot for the very first time on Central American soil, was the huge banner strung high above the terminal buildings at Nicaragua's main international airport.

"Welcome to Free Nicaragua!" it read in bright red letters.

It was 1986, seven years into the rule of the left-wing Sandinistas, who had toppled the Somoza dictatorship on a wave of popular support.

Meanwhile, leftist rebels in neighbouring El Salvador and Guatemala were locked in armed rebellion against US-backed regimes, trying to mimic the Sandinistas' success.

And in Washington, Central America had been declared the place where the line on communism in America's "backyard" would finally be drawn.

History was being made, lives were being changed.

World away

Eighteen years later, emerging once again into the heat of Managua's main airport, I came back to a country - and a region - a world away from those heady days of revolution and conflict.

My own reasons for coming to Central America in the first place had been a mixture of idealism and a thirst for adventure.

The radical agenda of the rugged-looking comandantes of the Nicaraguan revolution, pledging to create a "new society", caught my attention and curiosity.

So when the comandantes declared they were "under siege" from American-backed "Contra" guerrillas, and launched a plea for help across the world, I joined thousands of other Europeans and North Americans in heeding the call.

I was soon on a plane bound for Central America.

Together with a small group of other young men and women, I spent the following weeks struggling against the mosquitoes on a remote jungle hillside in northern Nicaragua.

We were the second British "coffee brigade" organised by the London-based Nicaragua Solidarity Campaign, dispatched to help bring in the harvest at the state farm of La Suana, in the coffee-rich Matagalpa province.

"I have finally arrived!" I wrote in my first letter home to my parents.

"Coffee picking is not hard, but is rather tedious. Conditions at the farm are harsh, the food not very appetising - rice, beans and large flat tortillas three times a day.

"But I am so glad to be here," I penned from my wooden bunk.

Legal limbo

Today, La Suana is no longer a state farm, and no longer harvests much coffee.

Since the fall of the Sandinista government in 1990 - defeated at the ballot box by a conservative coalition of opposition parties - many large estates have fallen into a legal limbo.

Their former proprietors - landowners who had fled the country and lost their properties in the early days of the revolution - are now back to reclaim their land.

When I returned there in mid-May this year, many of the men and women I had picked coffee alongside 18 years ago were camped out beside the Pan-American highway, to demand that the conservative government of President Enrique Bolanos grant them legal titles to land they had farmed during the Sandinista times.

"One of the great gains of the revolution was to get land," Evaristo Hernandez, one of the original pickers at La Suana, told me.

"With the passing of the revolution, we peasants have been abandoned by the authorities," he added.

Ironically, joining Evaristo and other poor peasant farmers in the protests were ex-Contras.

Former enemies, it seemed, have been united in a common struggle.

The ex-Contras were also promised land in return for giving up their weapons in 1990.

Capital changes

This sense of disappointment and broken promises reflected what I found from many of those I went back to see in post-revolutionary Nicaragua.

And not just in the countryside did I find how the changes.

The capital, Managua, used to feel more like a large village than a city.

Its simple roads, interspersed by green fields, were always free of heavy traffic.

Today, a giant statue of General Augusto Sandino - the legendary 1930s guerrilla leader who lent his name to the Sandinista revolutionaries - still towers above the city.

Successive governments have not bothered, or dared, to pull it down.

But gone are the long queues at the petrol stations, the crumbling supermarkets, stacked with Russian sardines and East German biscuits.

Now large luxury hotels and shopping malls take pride of place across the capital.

The streets and plazas that once bore the name of heroes of the revolution have long since been renamed.

Ortega

Despite the passage of time - it is 25 years this July since the Sandinistas overthrew the Somoza regime - many of the same familiar faces are at the helm of the Sandinista party, the FSLN, now in opposition.

Former President Daniel Ortega, despite accusations of corruption and cronyism, is still the party's general secretary.

Sergio Ramirez, who served as Mr Ortega's vice-president, told me that the veteran party leader was incapable of letting go of his dream of returning to power.

Mr Ramirez himself is now retired from politics to dedicate himself to writing novels.

"It is not the place that you and I knew 15 or so years ago," Dave Thomson, my guide around the capital, told me.

"Managua is definitely not the place to come to for fond memories," he added.

Staying on

Dave co-ordinated the coffee brigades, delegations and later a string of building brigades that came one after another to Nicaragua during the Sandinistas' 11-year rule.

But whereas I moved to El Salvador when the Sandinistas fell from power, Dave - a skilful craftsman and carpenter originally from Scotland - stayed on.

He now lives in a provincial town with his Nicaraguan wife, running a small organic farm.

"I stayed on for my own personal reasons. There were other things that kept me here, not just the revolution... my family, my kids," he said.

"When the Sandinistas lost the elections in 1990, I remember a lot of people suddenly felt that none of that experience in the revolution was valid. "But the important thing is to look at individual experiences; and now, little by little, people are realising that again," Dave added.

Mike Lanchin reported from Central America for the BBC in the 1990s.

This was the first part of his four-part series Legacies of Rebellion, which is being broadcast on BBC World Service on Mondays at 0805GMT.