Based on 5b, ex.4

Fill in: heart, port, road or track.
Idioms

1. It was with a heavy
   [ ] that I gave him such terrible news.
2. We left knowing we wouldn't reach our next
   [ ] of call for another week at least.
3. It's getting late. We'd better hit the
   [ ].
4. It might be off the beaten
   [ ], but it's a town well worth visiting.