A short walk from Pegsdon that takes in Knocking Hoe nature reserve. Although not that high gives excellent views across Bedfordshire, Hertfordshire and along the Chiltern Edge. It is worthwhile going on the site linked here this will tell you about some of the plants to view here.
While further along the walk you will visit Pegsdon Hills and Hoo Bit for more information check out the site here
If Neolithic sites are your thing then there are four here
Devils Ditch Earthwork (with a Roman Broach at its top (sadly, no surface evidence))
Knocking Knoll Long Barrow (best views from Knocking Hoe reserve) Round Barrow in Tingley plantation can be viewed in the woods from the Icknield Way next to the entrance of the Knocking Hoe reserve. Then near to the earthworks another round barrow at Telegraph Hill.
There are also numerous terraces along the Pegsdon Hills and evidence of chalk quarrying (used for lime, for both building and fertiliser