VISITORS to a science festival unearthed secrets beneath the streets yesterday.

Durham University is hosting a sidewalk safari as part of its four-day festival of science, engineering and medicine.

It offers visitors the chance to examine water bears, the tiny creatures, no bigger than the thickness of a human hair, which live between paving stones.

The bears are being extracted from their tiny moss forests along with other creatures, before being examined under a microscope.

The safari is among more than 20 hands-on activities being provided for school parties during the day and families in the evening. They include the opportunity to take part in a Trilobite Derby spanning several million years.

The free festival, which first started in 1995, is taking place in the School of Biological and Biomedical Sciences, off Stockton Road, in Durham.

It aims to increase awareness of and interest in science, and is expected to attract hundreds of schoolchildren.

Lorraine Jolley, masterclass and projects co-ordinator at Durham University, said: "The aim is to present students with a learning opportunity that will lead to an improved understanding of science and technology and at the same time, increase confidence in the students' ability to solve problems.

"The programme is very demanding, but experience has shown that motivated students respond well to this type of challenge."

The festival is open to the public until tomorrow, from 5.30pm to 7.30pm, while schools can attend until Thursday.