The few straight lines were introduced in the nineteenth century as attempts to impose order on this seemingly haphazard layout.
Cyflwynwyd y nifer fach o linellau syth a welir yn y bedwaredd ganrif ar bymtheg er mwyn ceisio rhoi trefn ar y cynllun trefol hwn sy'n ymddangos fel pe bai wedi digwydd ar hap a damwain.