rubberneck
1. [ noun ] a tourist who is visiting sights of interest
Synonyms: excursionist tripper sightseer
Related terms: tourist travel
2. [ verb ] strain to watch; stare curiously
Examples:

"The cars slowed down and the drivers rubbernecked after the accident"

Related terms: watch
3. [ noun ] a person who stares inquisitively
Related terms: spectator