scent
Ants follow a scent trail laid down previously.

blood, smoke, vapour/vapor
faint, thin
long
muddy
wet
false

lay, leave, make, produce
The couple laid a false trail to escape the press photographers.
The tourists left a trail of empty cans behind them.

find, pick up
The dog had picked up the trail of a rabbit.

notice, see
follow
lose
The fox had crossed a stream, and the hounds lost the trail.

cover

go cold
They had to find the kidnappers before the trail went cold.

on sb's trail
Detectives had found several new clues and were back on the murderer's trail.

a trail of blood, a trail of devastation
The hurricane passed, leaving a trail of devastation in its wake.

a trail of smoke

forest, mountain, nature, wooded, woodland
cross-country
10-km, 5-mile, etc.
bike, biking, cycle (BrE), hiking, jogging, mountain-bike, ski, snowmobile, walking
cross-country
tourist
This restaurant is off the tourist trail.

narrow, rough, steep, winding
dusty, rocky
dirt
lighted, marked, paved
groomed (AmE)
scenic
main
campaign, comeback, presidential, winning (BrE)
After a disastrous few seasons, the team are on the comeback trail.

follow, hit, take
I like to hit the trail early and be finished by eight.

hike, ride, walk (all AmE)
do (informal)
We did the Inca trail.

go, lead, run, wend its way, wind
The trail wends its way through dark forests.

begin, start
cross sth, follow sth, pass sth

along a/the trail

slowly
wearily
closely (behind)

after
I trailed wearily after the others.

around, round (esp. BrE)
They spent their lives trailing around the country.

(along) behind

badly
The team is now trailing badly in the league.
Tyler is trailing badly in the polls.

slightly

by
They were trailing by 12 points until the last few minutes of the game.

Trail is used with these nouns as the subject:
hand, ivy, wire

Trail is used with these nouns as the object:
finger