Tahrir Square is the symbolic heart of the Egyptian revolution the place where people stood united and faced down a ruler, a regime and a way of life to be rejected.

But now more than six months on, the square remains a focus of discontent, the home of protests of those who believe the revolution in Egypt didn't end in January but only began.

In the heat of the early morning, the check points on the roads into the square are already manned. The security is tense but polite and apologise for delaying our entry. More than once I'm told "welcome to Egypt.  The square itself is nothing special slightly weary, and run down.  I think at first it is an unremarkable place really in a country where history leaps out around every corner before quickly realising that this place too will join the storied and the famous.

There are thousands in the square for the latest Friday protest. The organisers predict more as the sun drops and the temperatures with it. The soft breeze from the Nile is welcome when it blows, finding its way past the mosque and the soon to be built luxury hotel.

The gathering brings together many layers of lie here - united in the view that the pace of change since the revolution is too slow, that too much of the old regime remains. The worries and concerns that brought them to the streets in January are the worries and concerns that drive them now.

And this they want the authorities to know is a final warning.

One man who travelled home from the US to take part in the revolution is still here five months on his life in America is as much on hold as the changes he craved in Egypt.

He says: “I'm here to see our demands realised. Nothing has changed since the beginning of the revolution."

One man has travelled for several hours to be in the square. He has an army boot on his head. He looks slightly crazed but his view is considered and thoughtful "We are still under the boot of the military and it has to change. You hear people chanting against them now".

Only this week the military led government forced 600 policemen into early retirement and made some concessions to the protesters but in the sermon ahead of prayers the words are angry even if the tone is not.

Sheik Mazar Shaeen is soberly dressed in grey with a red band around his hat. He speaks confidently and steadily. For him – to address the Friday crowds in Tahrir is a big moment. They listen attentively as he says what many are feeling: "They call us thugs for protesting but we are not. The government has made changes but why has it taken so long? Why didn't they do this months ago?"

And he warns the protests will grow once more if the government continues with what he believes is a reluctance to continue. “They must act, they must listen or the millions will return to the street”.

Some believe the government doesn’t want to move. They believe it is too firmly embedded in the economic life of Egypt, with its businesses and patronage, that it has too much to lose by changing too much.

In the tented village that has now become established in the roundabout in the centre of Tahrir there is a reminder of how deep the anger is, how far people will go to make their point.

Heba Fouad is a lawyer. She is helping to prepare sandwiches for the protesters but not one will pass her lips. She's now on hunger strike and says she will gladly die to highlight the demands of those in Tahrir.

"I have an important message I am against what is happening now. I want stability and prosperity in Egypt. If I can't have a decent life, death is better for me. If I cannot live as a free woman, then it's better to die as a hero."

The Arab spring has turned to summer. It has already changed the world - but for those here - the world hasn't changed quickly enough.

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