Sunset over the Sian Ka’An Reserve in Mexico. Taken from a boat on the 24/12/2012 at 18:23:39Hrs. Mexican Time. (0023 GMT), using a Nikon D3100 camera with a Tamron AF70-300mm F4-5.6 Di LD MACRO 1:2 lens. Sian Ka'an is a biosphere reserve in the municipality of Tulum in the Mexican state of Quintana Roo. It was established in 1986. Click on IMAGE or press L to view on BLACK. Right click on IMAGE & choose ORIGINAL for more detail.