Years ago, a local book dealer friend persuaded me to buy a set he had-
MARCH OF AMERICA FACSIMILE SERIES - 101 volumes.
Just the thing for history buffs.
Important books from Cristoforo Colombo Epistola de insulis nuper inventis, (Translation, of course), and Hakluyt, Diaz del Castillo, Drake, John Smith, Marquette- to Mackenzie, Pike, Fremont. Gregg and McCoy and Dimsdale (The Vigilantes of Montana, to Theodore Roosevelt (i>Ranch Life and the Hunting Trail.

I mention the last two because I actually read them; I read Gregg but just skimmed bits of the others.

Books I will never get round to reading.