Arecibo Observatory

The Arecibo Observatory sits a natural limestone sinkhole in the hills south of the town of Arecibo, on the north coast of Puerto Rico. A radio dish filled that bowl for decades, until the suspended platform above it came down in 2020. The site has now reopened to visitors as the Arecibo C3 STEM Center, and the preserved remains are visible from viewing areas on the hillside. Forested limestone hills circle the sinkhole, so a wide lens will give you the scale of the whole basin all at once. You can also experiment with something long so you can pull the surviving structures out against the trees. Clouds often build up over these hills throughout the afternoon and sit low, which will put texture in the sky above the rim. Rain is frequent and moves through fast. Tickets need to be bought in advance and the number of visitors each day is capped. It's best to take some time and research the rules for this area before you pack your kit because they are strict here. Tripods and drones are not permitted, and anything beyond a camera and lens needs authorization first. You can only view the remains from the marked areas. The whole property is a radio quiet zone by law, so phones must be put in airplane mode and Bluetooth turned off. (Arecibo, Puerto Rico, USA)