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)
Classic breakup line, and a hint to the formation of this puzzle's theme answers
Internet interjection found in two theme answers
Commonality of the theme answers
Nanobot's hypothetical ability, and the process that's overtaken this puzzle's theme answers
Finding from the "fifths" taken from this puzzle's theme answers
Struck out, as one letter in each of this puzzle's theme answers
Plummet ... or what this puzzle's theme answers do?
Title of a crossword with theme answers like OVERHAND KNOT, BUTTERFLY EFFECT, and CRAWL SPACE
Choice words swapped in this puzzle's theme answers
HBO's "Inside the __" (and hidden theme in this puzzle's four longest answers)
ConfuseÂ—or what to do to four common phrases to form this puzzle's theme answers
This puzzle's theme found in the answers to five asterisked clues
What presidential term limits mercifully ensure, and each of this puzzle's theme answers "receives"
What the puzzlemaker did to the name in each of this puzzle's theme answers?
Equipment for each of this puzzle's theme answers
Surplus integral to this puzzle's theme answers
New element in each of this puzzle's theme answers
What the theme answers have in common
Classic ad line, and question you need to answer to find the hidden theme in four starred answers
Alternative words used as alternatives for each other in this puzzle's theme answers
Rebelliously, perhaps (and a hint to this puzzle's four theme answers)
Reverend whose name is linked to terms like "Pazz and Jop," and this puzzle's theme answers
It may be involved in tallying the four theme answers
What this puzzle's theme answers start with