What do these signs indicate?

Explanation: If there's a bend or other obstruction concealing a level crossing, you won't be able to see the barriers, signals or any waiting traffic. Countdown markers, spaced equally at about 100 yard intervals, give you an early warning that you're approaching a level crossing, so you can be prepared to stop if necessary.

Category: Band 2 traffic signs and signals

References: Know Your Traffic Signs: Page 27