The Holiday Reveal:

2. A long hollow cylinder; or the colloquial name for the London Underground.
4. Adjective describing a route that offers beautiful natural views rather than speed.
6. Precious metal, chemical symbol Au; associated with 50th wedding anniversaries.
8. The Italian word for "Forward!"; also a UK high-speed rail operator.
10. Surname of the 19th-century American showman who founded a famous travelling circus.
11. The product of combustion; providing heat, light, and a cozy atmosphere.
12. Major London railway terminus serving the West Coast Main Line.
14. From the Latin for "circle"; a travelling company of acrobats and clowns.
16. A large vessel full of heated water, used for hydrotherapy or relaxation.

1. Waterfowl with webbed feet; the male is called a drake.
3. Hard grey sedimentary rock used with steel to produce sparks.
5. A hollow container used to shape molten liquid; or a fuzzy fungal growth.
7. To multiply by two; a doppelganger; or a standard measure of spirits.
8. A tributary of the River Dee; shares its name with a common male name (spelled with a Y).
9. A female imperial ruler; Queen Victoria held this title for India.
13. A portable shelter made of cloth, supported by poles and ropes.
14. Welsh word meaning a cubbyhole; now universally used to mean an affectionate hug.
15. A private room on a ship, or a small wooden shelter found in the woods.