to a specific country), as well as visas issued by each other, for stays of up to 90 days in a 180-day period (except for nationals of Turkey and Azerbaijan travelling to Cyprus). However, visas issued by Bulgaria, Cyprus or Romania are not valid for travel to the Schengen Area. The Schengen Convention and Schengen Borders Code permit member states to require third-country nationals to report their presence to a police station within 3 working days of crossing an internal border. This requirement varies by country and can usually be performed by hotels instead. The European Commission is planning to introduce a single online visa application platform at the EU level, replacing the separated national platforms. The platform will be built by eu-LISA and is scheduled to be introduced in 2026. A transition period for all member states to migrate to the single platform is scheduled to last until 2031. Visa facilitation agreements The EU has concluded visa facilitation agreements with several countries, which allow facilitated procedures for issuing visas for both EU citizens and nationals of partner countries. The facilitated procedures include faster visa processing times, reduced or no fees, and reduced list of supporting documents. These agreements are also linked to readmission agreements that allow the return of people irregularly residing in the EU. At the border In exceptional cases, single-entry Schengen visas valid for up to 15 days may be issued on arrival at the border. These visas are reserved for individuals who can prove that they were unable to apply for a visa in advance due to time constraints arising out of 'unforeseeable' and 'imperative' reasons as long as they fulfil the regular criteria for the issuing of a Schengen visa. However, if the individual requesting a Schengen visa at the border falls within a category of people for which it is necessary to consult one or more of the central authorities of other Schengen States, they may only be issued a visa at the border in exceptional cases on humanitarian grounds, on grounds of national interest or on account of international obligations (such as the death or sudden serious illness of a close relative or of another close person). In 2017, about 89,000 Schengen visas were issued to travellers on arrival at the border. People trying this way to travel to the Schengen Area can be denied boarding by the airline because of the carrier's