Bourn Brook, Cambridgeshire

Bourn Brook is a minor tributary of the River Cam in Cambridgeshire.

The brook has its source just to the east of the village of Eltisley, 10 miles west of Cambridge, where the hills rise to around 197 feet above sea level: lofty for Cambridgeshire. Minor tributaries known as the Eastern Brook, Hay Dean, Crow Dean and Gascote Dean merge just to the west of Caxton before it flows through Caxton, crossing the route of the ancient Roman road known as Ermine Street at its junction with the Bourn and Great Gransden roads.

A footpath follows the course of the brook from Ermine Street to the outskirts of the village of Bourn, where the Caxton End road crosses it by means of a ford. The brook then bisects the village of Bourn. The Bourn Brook is named after the village of Bourn, though the village in turn may be named form the brook, "bourn" being another word for a brook.^[1]

Flowing southeast from Bourn, the Bourn Brook runs through Bourn Golf Course where the Dean Brook adds its waters to the Bourn. Upon meeting the B1046 it turns east and runs alongside the former Varsity Line railway that closed in 1968. From this point until it reaches the River Cam it also forms the boundary between neighbouring parishes; of Kingston and Great Eversden to the south and to the north Caldecote and Toft.

After skirting the southern edge of Toft village, the brook crosses the Greenwich Meridian; here the old Varisity Line is now used as part of the Mullard Radio Astronomy Observatory; large parabolic dishes stand upon the track looking skyward. Comberton and Barton are to the north and Little Eversden, Harlton, and Haslingfield parishes to the south, but none of these villages stands on its banks.

Under the M11 motorway, the Bourn Brook passes between Grantchester and Haslingfield before flowing into the River Cam at Byron's Pool a few hundred yards south of the village of Grantchester; the pool where the poet Lord Byron is reputed to have swum.^[2]