CRPD/C/GC/2 equal basis with others. Article 9 has roots in existing human rights treaties, such as article 25 (c) of the International Covenant on Civil and Political Rights on the right to equal access to public service, and article 5 (f) of the International Convention on the Elimination of All Forms of Racial Discrimination on the right of access to any place or service intended for public use. When those two core human rights treaties were adopted, the Internet, which has changed the world dramatically, did not exist. The Convention on the Rights of Persons with Disabilities is the first human rights treaty of the 21st century to address access to ICTs; and it does not create new rights in that regard for persons with disabilities. Furthermore, the notion of equality in international law has also changed over the past decades, with the conceptual shift from formal equality to substantive equality having an impact on the duties of States parties. States’ obligation to provide accessibility is an essential part of the new duty to respect, protect and fulfil equality rights. Accessibility should therefore be considered in the context of the right to access from the specific perspective of disability. The right to access for persons with disabilities is ensured through strict implementation of accessibility standards. Barriers to access to existing objects, facilities, goods and services aimed at or open to the public shall be removed gradually in a systematic and, more importantly, continuously monitored manner, with the aim of achieving full accessibility. 15. The strict application of universal design to all new goods, products, facilities, technologies and services should ensure full, equal and unrestricted access for all potential consumers, including persons with disabilities, in a way that takes full account of their inherent dignity and diversity. It should contribute to the creation of an unrestricted chain of movement for an individual from one space to another, including movement inside particular spaces, with no barriers. Persons with disabilities and other users should be able to move in barrier-free streets, enter accessible low-floor vehicles, access information and communication, and enter and move inside universally designed buildings, using technical aids and live assistance where necessary. The application of universal design does not automatically eliminate the need for technical aids. Its application to a building from the initial design stage helps to make construction much less costly: making a building accessible from the outset might not increase the total cost of construction at all in many cases, or only minimally in some cases. On the other hand, the cost of subsequent adaptations in order to make a building accessible may be considerable in some cases, especially with regard to certain historical buildings. While the initial application of universal design is more economical, the potential cost of subsequent removal of barriers may not be used as an excuse to avoid the obligation to remove barriers to accessibility gradually. Accessibility of information and communication, including ICT, should also be achieved from the outset because subsequent adaptations to the Internet and ICT may increase costs. It is therefore more economical to incorporate mandatory ICT accessibility features from the earliest stages of design and production. 16. The application of universal design makes society accessible for all human beings, not only persons with disabilities. It is also significant that article 9 explicitly imposes on States parties the duty to ensure accessibility in both urban and rural areas. Evidence has shown that accessibility is usually better in bigger cities than in remote, less developed rural areas, although extensive urbanization can sometimes also create additional new barriers that prevent access for persons with disabilities, in particular to the built environment, transport and services, as well as more sophisticated information and communication services in heavily populated, bustling urban areas. In both urban and rural areas, access should be available for persons with disabilities to the natural and heritage parts of the physical environment that the public can enter and enjoy. 17. Article 9, paragraph 1, requires States parties to identify and eliminate obstacles and barriers to accessibility to, inter alia: 5