Found in Preston in 1793.
Interpreted in 1961 by A. Simons
1793, 3-couple set, longways Repeat dance three times.
Recording: trip_to_tunbridge-069-bn13mbt-11.mp3.zip
trip_to_tunbridge--0.mp3.zip
trip_to_tunbridge--010.mp3.zip

A1 1-8 1’s cast down the outside to the foot, “take a peek”, then
       dance back to the top.
A2 1-8 1’s dance down the center, then turn towards each other
       to face up, skip to the top, separate and cast around
       the 2’s (2’s pause, then lead up.)
B1 1-4 1’s pass R-shoulder, then R-hand turn 1st corner.
   5-8 1’s pass R-shoulder, then R-hand turn 2nd corner.
       1’s pass R-shoulder again, to end in middle place facing
       out (Others turn and face out to make two lines-of-3.)
B2 1-4 Lines-of-3 lead out a double and fall back, turning to
       face partner just at the end.
   5-8 2’s at the top 2-hand turn 1x. 1’s in middle place dance a
       long cast to bottom. 3’s in bottom place 2-hand turn
       moving up to middle place.

Video: http://dancevideos.childgrove.org/ecd/playford/248-trip-totunbridge

Walsh 1728
Longways Triple Minor

Al 1-4 1st couple cross outside 2nd couple, giving nearest hand to neighbor,
       turn once and a half (1st man 2nd lady right hands, 1st lady 2nd man
       left hands)
   5-8 1st couple two hand turn to finish facing each other (improper) between
       the 3rd couple
A2 1-8 1st and 3rd couples hey across, 1st couple start passing by the right
Bl 1-8 1st couple set right and left, 1st man casts down below the 3rd couple
       to make a circle with them, while 1st lady casts up above the 2nd
       couple to make a circle with them, all circle left halfway
B2 1-8 1st couple meet in the middle and right hand turn halfway, 1st man
       casts up, while 1st lady casts down, all circle left halfway with
       counter couple finishing in progressed places.

Video: https://www.youtube.com/watch?v=YpGGSrkuVdA
As someone born in Tunbridge Wells, I'd spell it “Tonbridge”. But that's because Tunbridge became Tonbridge in 1870.–NashJc 17:25, 21 March 2010 (EDT)