The history hunters have been working at the site of the Greek Orthodox Church at Sutton Farm, Shrewsbury while a new housing development takes shape.
And they had until late yesterday to find, catalogue and photograph the objects, which have included a number of animal burials, a coin dating back to the time of Charles I, medieval artefacts and a Stone Age flint.
Housing developers Taylor Wimpey are building almost 300 houses on land surrounding the church and while the grade II-listed building, which is also known as the Church of the Holy Fathers, isn't being knocked down, a field adjoining it is earmarked for a car park.
Janey Green, from Baskerville Archaeological Services, said: "We have been here since the later summer and it has been a real treat. You never know what you are going to uncover.
"We knew there was a potential for human burials and there were rumours of a porch area out beyond the existing church. But we never expected to find there was a building extending out a further 17 metres, so that was a complete surprise. We believe this is an Anglo Saxon church with a late medieval addition.
"The size of it means this was a very important church. But it is the burials that are the most intriguing. We have a calf and a pig that were carefully laid beside each other in a symmetrical shape. A Stone Age flint was recovered between the ribs of the calf.
"Other significant finds include three small garment pins and a carved stone that could be Iron Age, Roman, Anglo-Saxon or early medieval."
A wedding is due to take place at the church on Sunday and the area needs to be covered to enable the wedding party to gain access to the church.
Funds aren't available to enable the excavation to be uncovered again and allow archaeological work to continue. A special funeral service will be held at the church to rebury the bones of the people and animals uncovered.