for (e.g. "pay and display" or parking meters). There may be a time limit on the period of stay and a minimum time before returning to a particular parking place. Where a plate does not indicate the days of the week, the restrictions apply at the same times on every day, including Sunday. Where the time of day is not shown, the controls apply for 24 hours. If a bank holiday falls on a day when the controls are in operation, the controls apply in the normal way unless the plate states that they do not. Special restrictions may apply on days when a large event is being held. Motorway signs For use on busy motorways and other wide roads where verge mounted signs would be frequently obstructed by other traffic. An advance direction sign (ADS) generally has blue, green or white as its background colour to indicate the status of a road (motorway, primary or non-primary) on which it is placed. Except on the main carriageway of a motorway, coloured panels are used to indicate routes from the junction being signed that have a different status. A direction sign (DS) should always be a single colour indicating the status of the road to be joined, although there are a few rare exceptions to this rule. The Heavy and Medium typefaces were designed to compensate for the optical illusion that makes dark lines on pale backgrounds appear narrower than pale lines on dark backgrounds. Hence destinations are written in mixed case white Transport Medium on green and blue backgrounds, and in black Transport Heavy on white backgrounds. Route numbers are coloured yellow when placed directly on a green background. Some signs logically show the closest destination on the route first (i.e., on top), while others show the most distant settlement first. On a roundabout DS, the route locations are usually listed with the closest destination at the bottom and the furthest away at the top when going straight ahead, and likewise going left and right. However, many left-right signs more logically indicate the closest destination at the top with further afield destinations listed in descending order. Destinations and roads which cannot be directly accessed on a driver's current actual route, but can be accessed via an artery route of that carriageway, are displayed in brackets. All types of ADS (but not DS) may optionally have the junction name at the