Investigations of deposits at a built-over site near the centre of Liverpool disclose a basal stratigraphic sequence characteristic of the west-European Late-glacial period. Detailed pollen analyses confirm that the deposits extended from the Late-glacial (Zone I) to the Post-glacial thermal maximum (Zone VIIa). The lake was overgrown in Zone VI by floating Sphagna, and in Zone VII a typical raised bog developed. Macroscopic remains of lake and fen plants were recovered in great abundance and together with frequent non-tree pollen these permitted a detailed reconstruction of the vegetational history of both the lake and the surrounding upland. Several species of notably disjunct or restricted present-day range have been recorded here, Cotoneaster cf. integerrima Medic., Elatine hexandra (Lapierre) D.C., Lycopodium annotinum L., Pilularia globulifera L., and Linum anglicum Mill., whilst tentative identification of species such as Agropyron junceiforme, A. & D. Love, Gentiana campestris (L.), Lotus uliginosus Schkuhr, and Vicia sepium L. cast new light on the natural status of other British plants. Numerous further records confirm and extend our knowledge of the history of the British flora, especially in the Late-glacial and early Post-glacial periods.