This is just one of the fascinating places in Oxford that rarely gets into the guide books - perhaps because science is not perceived as mainstream visitor attraction - and let's face it, Oxford has a lot of attractions that are easier on the eye and the mind. Even here, you could easily pass this exhibit by, as there is no plaque or information panel to explain it. In fact very little in this packed three-storey museum is explained, which is its one drawback.

The museum's basement is like Frankenstein's Laboratory, with countless glass containers full of strange objects and all manner of inexplicable but worrying tubes and medical instruments. Perhaps the lack of a precise description is no bad thing, after all!

At the information desk on the ground floor, a leaflet is available which suggests a walk around the major scientific landmarks in Oxford. Turn right out of the museum, right again and then left into New College Lane and you will come to the house at No 7 where the astronomer Edmund Halley lived. Mainly known for predicting the orbit of the comet that bears his name, Halley was a pioneer in many fields, including the optics of rainbows. The roof of his small house (now used for student accommodation) is topped by a little pepper-pot observatory where Halley used to stargaze at night.

Continue winding your way along New College Lane and after the fourth bend in the lane you will pass the church of St Peter-in-the-East, where James Sadler, the first English aeronaut is buried, renowned for his ballooning feats in the late-18th century.

At the High Street, turn left to get to the Botanic Garden, a short way down the road on the right. The garden was founded in 1621 and the first head gardener insisted that 4,000 loads of 'mucke and donge' be spread upon the site. His foresight paid off, as herbs and plants with medicinal and scientific uses have flourished here ever since. At this time of year the garden is a delight to walk in, and even when it is cold, there are several greenhouses to explore, containing all kinds of exotic species.

As you leave the garden look for the stone memorial outside. This commemorates one of the most significant scientific discoveries of the twentieth century: Sir Alexander Fleming's discovery of penicillin in 1928, for which he won the Nobel Prize.

Head left back up the High Street and see if you can spot the plaque that marks the place where Robert Boyle and Robert Hooke had their laboratory. Boyle is known to every schoolchild for Boyle's Law, which governs the inverse relationship between the volume and pressure of a gas. Hooke was Boyle's assistant and inventor of the first compound microscope.

But enough of old science - what we want is something new. And what could be more state of the art than big bangs, black holes and quantum theory. Eyes left on the High Street for University College, whose most famous recent undergraduate is Stephen Hawking, famous for his work on the origin of the universe, and his brief, if densely packed, history of time.

Almost opposite is the entrance to All Souls College. Take a look in the Great Quad to see a sundial that was designed by Sir Christopher Wren, best-known as the architect of Oxford's Sheldonian Theatre, not to mention St Paul's Cathedral and a hundred City of London churches. This is where Wren's career began - as a mathematician first, then appointed in 1661 as a precocious thirty-year-old Professor of Astronomy.

Two blocks behind University College is Merton, founded 1264 and soon established as the foremost science college of the age. One notable Warden of the College was William Harvey, who discovered that blood circulates around the body through the pumping of the heart.

Merton also has the oldest quad in Oxford (Mob Quad), and its 14th century Old Library is the oldest library in Britain still in daily use. Tours are available, though there is no guarantee you will see one of the library's most famous features: its resident ghost. After all, that would not be very scientific, would it?