Green’s Dictionary of Slang

harbour (of hope) n.

[idea of the penis sheltering]

the vagina.

[UK]Congreve Love for Love III i: Mayhap I may steer into your harbour. How say you, mistress?
[UK]S. Centlivre Basset Table Act II: I [...] Am too well acquainted with the Dangers of Rocks and Quick-sands, to steer into t’other’s Harbour.
[UK]Farmer & Henley Sl. and Its Analogues.