Due to the recent advances in ultra high definition (UHD) displays, UHD TV may replace HD TV in a near future. However, little is known about the effect of UHD content on human visual perception, specifically, on human visual attention, viewing strategies, and visual saliency. To help studying these properties of the human visual system and their dynamics when HD content is replaced with UHD content, a publicly accessible dataset is proposed, which is composed of 41 4K UHD and HD images with corresponding eye tracking information. The eye tracking information includes the fixation points and fixation density maps measured during extensive subjective experiments. In this paper, we describe the dataset in details, including the strategy for content selection, the eye-tracking experiments, and the computation of the fixation density maps.