Transport systems that begin each of the three theme answers

Question:

Answer:

SUBWAYS

Length:

Similar Crossword Questions:

Number of times this puzzle's theme word appears diagonally in the grid (to complete the puzzle, shade those words plus the Down answers that begin where they meet)
Big fight, and clue to this puzzle's theme that begins the four longest answers
Term for each of the 15 asterisked theme answers in this puzzle
Where everything from the theme answers collects
Typical number of theme answers in a crossword
They swing up and down in this puzzle's theme answers
When spelled out, word that follows the beginnings of the starred answers in a memorable kids' show theme song
Proper sort ... or a cry upon solving each of this puzzle's theme answers?
Word before the first word in this puzzle's theme answers
The pairs of letters inserted into each of this puzzle's theme answers, for example
Reservoir, and hint to puzzle theme found in seven long answers
Devices that, when turned, adjust themselves (just like the theme answers)
Word appearing in all nine theme answers
Classic breakup line, and a hint to the formation of this puzzle's theme answers
Grate, with "get," or what this puzzle's theme answers get
Rumored reason for the stock market plunge of 5/6/10, whose effect is seen in this puzzle's theme answers
Choice words swapped in this puzzle's theme answers
HBO's "Inside the __" (and hidden theme in this puzzle's four longest answers)
Out of whack, or what's featured in each of this puzzle's theme answers
ConfuseÂ—or what to do to four common phrases to form this puzzle's theme answers
Theme of this puzzle hidden in the seven other longest across answers
Element of surprise in this puzzle's theme answers
Weather Channel feature (it's the puzzle theme found in a quintet of answers)
Theme park transport
Internet interjection found in two theme answers