A friend and I will attempt a century this Saturday through the Negev Desert to a southern beach resort in Israel. My wife and kids will provide sag support with our car.

I'm thinking back to my last century probably 20 years ago (and the three before that) and I don't remember that any of them finished before it started getting dark. The plan is to start riding at 7am. It's a mostly downhill course while my other ones rolled through the Philly surroundings. My ride app says 3000ft up and 5600ft down. My normal 21mile training ride is already 1700ft up and down so I'm hoping 3000ft feels like nothing. It's that last 40 miles of flat I'm worried about.

How many of your centuries ended with plenty of light to spare? I'm wondering if I should strap the headlamp onto my helmet now or wait and see. It's not a bike specific light so the battery pack (4 AAAs) would sit on the rear of the helmet. It probably wouldn't bother me for a short ride, but might start to hurt my neck.