FL310
Sorry, but Concorde did not fly in 1967.
The first flight was on the 02 March 1969 when Concorde 001, F-WTSS, under the command of Andre Turcat, Director of Flight Test at Sud Aviation, took off from Toulouse.
The first flight of a British Concorde, as you rightly say, was some five weeks (and nine flights by 001) later on 09th April 1969, when Concorde 002, G-BSST, under the command of Brian Trubshaw, Chief Test Pilot for BAC, took off from Filton, landing at Fairford.
Both were beaten by the Russian TU 144, which first flew on 31st December 1968.
[This message has been edited by Bellerophon (edited 02 January 2001).]