If you are considering walking this route yourself, please see my disclaimer. You may also like to see these notes about the maps and GPX files.
When I've walked through here before I've only gone as far as a parking area on the right, where a footpath goes off on that side, but today I continued to the end of the drive, where I turned right into the car park for the nature reserve. Two paths led off from the far side of the car park - I've taken the one on the right both times I've been here before to look for butterflies, but today I took the one further left. This went through part of a wood and then joined a 'hollow way' or 'sunken lane' that dropped downhill through a tree belt. Unfortunately I was now very close to the M40 (which divides the nature reserve in two!) so I had to put up with the constant drone of road noise. At one point I got a view out over the M40 and the Oxfordshire Plain beyond.
The drive to the Aston Rowant nature reserve car park
The drive to the Aston Rowant nature reserve car park
The path from the Aston Rowant nature reserve car park
The path from the Aston Rowant nature reserve car park
The path from the Aston Rowant nature reserve car park
View out to the M40 and the Oxfordshire Plan from the path from the Aston Rowant nature reserve car park
Eventually the path left the tree belt. It was now quite delightful (or would be without the road noise!) as the embankments either side were covered in wildflowers and there were a few butterflies flying around, including some rather tattered Chalkhill Blues. After a while I followed the chalky path up the embankment on the right and on to a gate. On the other side of the gate the path forked, and I took the left fork (the right fork went uphill and curved round to eventually go back to the car park). The path very gently descended at the foot of a steep grassy hill, again with plenty of wildflowers and a few butterflies. I was delighted to see some Adonis Blue butterflies, they were instantly recognisable because they are such a stunning shade of blue. I knew they were to be found here, though the only place I'd seen them in the Chilterns before was at Yoesden (so I no longer needed to look for them there on my way back, as I'd planned). But there was no sign of Silver-spotted Skipper butterflies, which I'd hoped to see here. Eventually, after going through a small area of trees, the path turned left and went through gates either side of a small enclosure (there was an information board about the Aston Rowant nature reserve here) to reach the Ridgeway national trail.
The path from the Aston Rowant nature reserve car park
The path from the Aston Rowant nature reserve car park
The path from the Aston Rowant nature reserve car park
A very worn Chalkhill Blue
The path through the Aston Rowant nature reserve after I went through a gate and forked left
Further along the same path
Further along the same path
Further along the same path
Further along the same path (just before it turns left)