The only place with no speed limit... not a racecourse but a public countryside roads.
Since the start of the race 240 deaths so far. The TT races are extremely dangerous because riders achieve high speeds on very narrow, twisting streets, roads and lanes flanked by stone walls and buildings.
No room for error.
[youtube]http://www.youtube.com/watch?feature=player_embedded&v=D09yD0MN4Vg#at=652]http://www.youtube.com/watch?feature=player_embedded&v=D09yD0MN4Vg#at=652[/youtube]