On 12 February 1986, at Canterbury, the Treaty between the United Kingdom and the French Republic concerning the Construction and Operation by Private Concessionaires of a Channel Fixed Link was signed. Plenipotentiaries, according to UNTS I-25792: Sir Geoffrey Howe and Roland Dumas. Wikipedia adds the presence of Thatcher and Mitterrand and places the ceremony in the cathedral; the instrument is done at Canterbury. Authentic texts: French and English, equally authoritative. Deposit of ratifications at Paris; Article 20: entry into force on the exchange of instruments — 29 July 1987. Registration by France on 16 March 1988, volume 1497.

Article 1: the Parties undertake to permit construction and operation by private concessionaires, without recourse to government funds or guarantees. The Fixed Link: a twin bored rail tunnel, with an associated service tunnel, between Cheriton in Kent and Fréthun in the Pas-de-Calais, together with the terminal areas. This is not a construction handbook. The Concession between the two Governments and the Concessionaires, signed on 14 March 1986, is a distinct later instrument.

Article 3: the frontier in the Link is the vertical projection of the line in the Agreement signed at London on 24 June 1982 relating to the continental shelf east of 30 minutes west of Greenwich. A Joint Commission shall mark the frontier in the tunnel before the Link comes into operation. Article 4 leaves frontier controls to a supplementary protocol — without control procedures. The 1982 maritime agreement remains a separate treaty.

Article 10: an Intergovernmental Commission shall supervise, on behalf of the two Governments, all matters associated with construction and operation; decisions are taken by agreement between the heads of the British and French delegations. Article 11: a Safety Authority advises it; each Government appoints half the members; the chair alternates annually. This is not an emergency rulebook. Article 19: disputes not settled through the consultations in Article 18 go to an arbitral tribunal; the President of the Court of Justice of the European Communities may make fallback appointments.

Article 12 recognises the Concessionaires freedom of management within the Concession. Article 13: adequate insurance; liability according to the law of the part of the Link where the event occurs. Article 16: compensation between States if one unilaterally interrupts construction or operation. The instruments DONE formula is not copied.

The tunnel opened to traffic in 1994. Later protocols on juxtaposed controls and the extension of the concession to 2086 are distinct acts, not this treaty.

Cover: Canterbury Cathedral, the place of the ceremony according to Wikipedia — the photograph is of the building, not the table. Wikimedia Commons, free licence.

For context: Treaty of Canterbury (1986). The text: Treaty concerning the Construction and Operation by Private Concessionaires of a Channel Fixed Link (UK Treaty Series).