The notion of regional lockdown and quarantine (derived from the Italian word for 40 days) is not new, it was practiced from biblical times to the plague outbreaks of the Middle Ages and later. However, in the middle ages the country was an agrarian economy without the transport links of the 21st Century. The correlation of Covid deaths and population distributions illustrated in the maps below, is plainly apparent.
The UK is a small country in which the majority of the population live in an area approximately 200 miles long by 70 miles wide, illustrated by the rectangle on the maps. This area also contains the bulk of the main transport hubs. Therefore the 21st Century version of local or regional lockdown has far more variables than did previous cases and the notional of regional or even city lockdown might prove illusory.
However, regional, or local lockdown does make some sense, but only if it can be rigorously enforced and this degree of enforcement is questionable at best. The comparisons with the story of the village of Eyam in Derbyshire in 1666 is well worth consideration as the parallels are very evident.¹
¹https://www.rte.ie/brainstorm/2020/0428/1135297-eyam-great-plague-coronavirus