Sir – I would have hoped that Chris Payne (Letters, August 16), who describes himself as the former beat officer, might be better acquainted with the law.

Cycling through the subways at Green Road roundabout is not an offence: it is not alongside a roadway, so the 1835 Act does not apply.

There are no traffic restriction orders in place. The “Cyclists Dismount” signs have no legal meaning and do little more than cack-handedly highlight a potential hazard.

The main legal restraint is that cyclists are not allowed to ride carelessly or inconsiderately. Rather than seeking to prosecute cyclists for non-existent offences, we should be trying to find ways to rectify the mistakes of our forebears in building such confined subways.

While the subways themselves are too expensive to alter, the approaches can be altered to remove tight and blind corners and make it easier to ride considerately. In particular, the zig-zag ramp on the north-west side of the roundabout should be opened out, to make a good route from Headington to Barton.

Richard Mann, Cyclox