Both dawn and dusk are some of the best times of the day for photography. The colours and contrasts are sometimes truly amazing.
I took this shot today. It was a cold morning at 07:30 and the image is of several kayakers on the river Derwent and the rich colours of the sunrise. Camera specs: Nikon D700, 1/640sec at f/6.0, ISO 200, 135mm (Tamron 28-300mm)