Way of the Rings Chipping Norton to Stonehenge ng Norton)
This  90mile (148km) route is the final segment of The Way of the Rings a 555km route from Castlerigg Stone Circle in the Lakes to Stonehenge, passing through or near Neolithic and historic sites of interest.  It traces a probable route taken by Neolithic people  who journeyed with their pigs and cattle to Stonehenge for the Winter Solstice.
This can be done over 1-2 days taking in each of these sites:
Rollright Stones (near Chipping Norton) The Rollright Stones is an ancient site located on the Oxfordshire & Warwickshire border in England. The complex consists of three main elements, The Kings Men stone circle, the King Stone, and the Whispering Knights.
Blenheim Palace - through the grounds;  Blenheim Palace a World Heritage Site with over 300 years of History and home to the 12th Duke of Marlborough and his Family. A Historic House and Gardens in Oxfordshire.
Uffington White Horse - The Uffington White Horse is a prehistoric hill figure, 110 m (360 ft) long, formed from deep trenches filled with crushed white chalk. The figure is situated on the upper slopes of White Horse Hill  which the route passes.
Stanton Harcourt - The Devil's Quoits, a henge monument  was used throughout the late Neolithic and Beaker periods, and comprised an embanked stone circle c. 280 ft. across, composed of 30 or more stones; it was mostly destroyed in the Middle Ages to make way for cultivation, some of the stones being broken and possibly re-used in Stanton Harcourt church.
Avebury - Avebury is a Neolithic henge monument containing three stone circles, around the village of Avebury.  One of the best known prehistoric sites in Britain, it contains the largest megalithic stone circle in the world.
Durrington Walls - Durrington Walls is the site of a large Neolithic settlement and later henge enclosure located in the Stonehenge World Heritage Site., 2 miles (3.2 km) north-east of Stonehenge.
Woodhenge - Woodhenge is an atmospheric Neolithic site close to Stonehenge. Probably built about 2500 BC, it was originally believed to be the remains of a burial mound, surrounded by a bank and ditch almost completely destroyed by ploughing.
Stonehenge - the start or end of the route - Stonehenge is a prehistoric monument in two miles (3 km) west of Amesbury. It consists of a ring of standing stones, each around 13 feet (4.0 m) high, seven feet (2.1 m) wide, and weighing around 25 tons. The stones are set within earthworks in the middle of the most dense complex of Neolithic and Bronze Age monuments in England, including several hundred tumuli (burial mounds). Archaeologists believe it was constructed from 3000 BC to 2000 BC.
The route can be riden N-S or vice versa.  There is accommodation throughout and superb country pubs.
Transport - train station at Salisbury (direct service to London) and Pewsey.  There is transport to Stonehenge and from Stonehenge (but not bike-friendly) so this would mean leaving bikes locked at Stonehenge and taking transport to Salisbury Train station to pick up car etc.  If the route is undertaken over 1.5-2 days there is the option for train services from Oxford to  Salisbury (via Reading and Basingstoke).