“The Prisoner of Zenda" by Anthony Hope. A good enthralling read.

"The Man in the Iron Mask" by Alexandre Dumas.

"The Scarlet Pimpernel" by Emmuska Orczy.

"Captain Blood" by Rafael Sabatini.

Any of Jules Verne's, 'Extraordinary Voyages' books - A Journey to the Center of the Earth", "Around the World in 80 Days", "Twenty Thousand Leagues Under the Sea". There are many more lesser known also.

I tried to go for old interesting classics you may not have read. I enjoyed them all myself. Some nice plot lines, twists and turns etc.

I hope with the recommendations from everyone, you at least can pass your time away quicker. Good Luck.