While there is no clear statutory definition of a highway, at common law, a highway is a route along which people can pass and re-pass at all times as frequently as they wish without hindrance or charge. As, by definition, a highway must be open to all, a private highway cannot exist and all highways are therefore ‘public’ . A highway can be unadopted and therefore privately maintainable but the rights of the public to use such a highway are the same as if it were adopted and therefore maintainable at the public expense. There are also various classifications of highway, with the most commonly encountered being roads, footpaths and bridleways  but there are well over 30 classifications, including the quaintly named ‘quiet road’.
Extent of a highway
The main access issues encountered on land acquisitions relate to the extent of a highway with the predominant concern of many buyers being whether their land abuts, or takes access directly from, an adopted highway. Whilst this seems a relatively straightforward question, it is not always as easy as one might think to ascertain the exact extent of land to be acquired and where the adopted highway begins.
The legal boundary of land in private ownership is often difficult to ascertain primarily because ‘boundary’ has no specific legal meaning. To determine a boundary two matters must be considered, first the legal boundary, which is unlikely to be accurately identified in the deeds to a property and, secondly, the physical boundary, be it a fence, wall or other feature. Title plans obtained from the Land Registry are of little help in determining the legal boundary since almost all Land Registry title plans are prepared under the ‘general boundaries rule’  which provides that a boundary of a registered estate is a general boundary unless it is shown as having been determined by an application to fix the boundary.
In many cases the most that can be done is a comparison of the title plan for the land to be acquired as against plans provided by the highway authority showing the extent of the adopted highway. If in doubt, inspection of the site and the highway is imperative as it can provide information that could not be obtained from reviewing plans alone. For example, where it appears that land adjacent to the highway itself is being maintained by the highway authority then it is probable that it was part of the land that was dedicated, and therefore forms, part of the highway. Boundary features at the sides of the highway may also provide an indication that everything between those features forms part of the highway. It should also be borne in mind that where a highway adjoins land the adjacent land owner is presumed to own the subsoil of the highway to the midpoint (the ‘ad medium filum’ presumption). This presumption may be helpful in certain circumstances, albeit it can be rebutted and is not a universal panacea to access issues.
As to the vertical limits of a highway then, notwithstanding the ad medium filum presumption, statute confirms that not only is the surface of the road vested in the highways authority, but also sufficient soil beneath it and air above it to provide for the highway . Overhanging a highway is prohibited without consent and, as such, when developing land adjacent to a highway it is important to ensure that not only the footprint of the building, but also anything which may project from it, for example gutters or balconies, are kept within the boundaries of the development site.
Formation of a highway
There are a number of ways in which a road can attain the status of a highway, with one of the most common being by dedication pursuant to a section 38 agreement  as a result of the development of new residential or commercial estates. Highways can also be dedicated pursuant to section 37 of the Highways Act 1980 (HA 1980), by express or presumed dedication at law, utilising the highway or local authority power to construct under section 36(2) of the HA 1980 and also by ancient use.
Dedication pursuant to a section 38 agreement occurs when a developer agrees to construct roads to adoptable standards as part of a development and the highway authority confirms that it will accept the dedication and become responsible for future maintenance of the road at the public expense.
A section 38 agreement generally contains step-in rights allowing the highway authority to carry out works and recover the costs of doing so in the event that the developer defaults. The agreement is usually supported by a bond from a bank or insurance company to ensure that if the step-in rights are exercised the highway authority can recover the costs of undertaking the works. Agreements can also contain wide obligations as to payment of expenses that have been used to allow highway authorities to recover commuted sums for the estimated costs of future maintenance .
A person who wishes to dedicate a road as a highway maintainable at the public expense, provided that they own the road in question, can do so voluntarily by serving notice to the highway authority under section 37 of the HA 1980. This provision, which can be useful if a developer and a local authority have been unable to agree the terms of a section 38 agreement, permits a developer to give notice to the highway authority not less than three months before the proposed date of dedication that it wants the highway to be adopted. The authority then has two options. First, it could certify that it has been dedicated and constructed to satisfactory standards and provided that the developer then keeps it in repair for a period of 12 months and the highway has been used in that period it will become maintainable at the public expense. Alternatively, the authority may object in the magistrates’ court on the basis that the highway will be of insufficient utility to the public to justify its adoption. If authority does not certify that it accepts the dedication the developer may itself apply to the magistrates’ court against the refusal and the court has the discretion to make an order deeming such a certificate to have been issued.
Highways can also be created by dedication at law. Such dedication can be express, albeit presumed dedication either at common law or by statute under section 31(1) of the HA 1980 is more common. There are two stages to such dedication, the dedication by the landowner and subsequent acceptance by the public. The common law presumption is that land will have been dedicated as a highway if it has been used by the public ‘as of right’ and ‘without interruption’. Use does not have to be for a defined period of time, but must be sufficient to justify an inference that the owner intended to dedicate it as a highway. Hence where an intention to dedicate can be proved, short periods of use may lead to creation of a highway.
The statutory process under section 31(1) does not replace the common law but does provided that dedication will be presumed if the highway has been used by the public as of right and without interruption for 20 years and it is not of such character that public use cannot give rise to a presumption at common law of dedication.
For both the common law and statutory presumption to arise, use must be as of right. As with prescriptive easements use must be without force, stealth or permission . Therefore, if a landowner maintains a notice which is inconsistent with dedication of a highway this will generally be sufficient evidence to rebut an intention to adopt as a highway. In addition, landowners can use the procedure in section 31(6) HA 1980 to deposit a map showing any roads which the landowner admits to having been dedicated. Lodging a statutory declaration within 20 years of such a deposit confirming that no additional dedication has taken place, in the absence of any evidence to the contrary, is then sufficient to negate the intention to dedicate any other roads as highways.
Finally, it should be noted that any road constructed by the highway authority becomes a highway maintainable at the public expense. A highway authority cannot compel a landowner to dedicate a right of way across its land and therefore the authority must either acquire the land by agreement or by exercising its power to compulsorily purchase.
It is clear that whilst the question ‘does my land have adequate access’ is a simple one, the answer is often difficult to establish. The application of the general boundaries rule means that it can be very difficult to confirm accurately whether land to be acquired actually abuts the adopted highway. Circumstances surrounding maintenance of land adjacent to the highway, and the application of the ad medium filum presumption may provide some comfort but it may not always be possible to provide a conclusive answer to the very simple question asked. Should it be necessary to consider the dedication of a new highway to provide access to land that is being acquired this can be done in a number of ways. The most common is an agreement under section 38 of the HA 1980 but there are other ways in which a highway can be dedicated, for example under section 37 HA 1980 or by presumed dedication.
 Roads and footpaths unlike highways can be public or private and it is, of course, possible to have a private right of way.
 A road is defined by statute as a highway or other road to which the public has access and includes bridges over which roads pass (section 142 Road Traffic Regulation Act 1984 and section 192 Road Traffic Act 1988). A footpath is a way over which the public have a right of way on foot (and is not a footway) (section 66, Wildlife and Countryside Act 1981). The public have rights of way on foot, bicycle and on horseback over bridleways and may also lead horses over them and some bridleways include a right to drive other types of animal along them (statutory definitions of a bridleway are contained in both sections 329 of the Highways Act 1980 (HA 1980) and section 66 of the Wildlife and Countryside Act 1981 with cyclists rights to use bridleways being contained in section 30 of the Countryside Act 1980).
 See section 60 of the Land Registration Act 2002
 Section 263 HA 1980
 Section 38 HA 1980
 See Redrow Homes Ltd, R (on the application of) v Knowsley Metropolitan Borough Council  EWCA Civ 1433 where the Court of Appeal determined that provisions in section 38(6) HA 1980 allowed the recovery of future maintenance costs.
 Nec vi, nec clam, nec precario.