| Answer | Crossword Clue |
|---|---|
| TRAM | One going through a tunnel, perhaps |
| RIFLER | One going through papers in a safe, say |
| ALP | St. Gotthard Tunnel passes through one |
| PETEACHER | One going through the exercises? |
| DECLARER | One going through Customs, e.g. |
| MOUNTAINBIKER | One going through cyclic ups and downs? |
