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We present BVR CCD photometry of stars in the Leo I dwarf spheroidal galaxy. The color-magnitude diagram of Leo I is different from that of any other dSph studied to date. The stellar population also contains a variety of clues about the differences between Leo I and other dSph galaxies.
The giant branch in Leo I shows a spread in color which is larger than can be accounted for by observational errors alone and is most likely the consequence of the giants in Leo I having a range of metalicities.
The identification of a feature in the color-magnitude diagram consisting of a well populated clump adjacent to the giant branch with a sparse extension into the blue as the horizontal branch is confirmed by the presence of RR Lyrae variables at the feature's blueward edge. The red clump pushed into the red giant branch is an indicator of ``young'' age (by globular cluster standards). The horizontal branch in Leo I displays significant scatter in both magnitude and color and probably indicates both a range of age and a range in metalicity. Extensive artificial star tests confirm the reality of the color and magnitude spread.
Leo I also possesses a significant population of stars more luminous than the horizontal branch and bluer than the giant branch. This blue population includes a number of anomalous cepheids and points to the presence of a substantial intermediate age population.
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