The small but interesting Muisca Observatory located just outside the town of Villa de Leyva in Colombia has about 100 carved stones erected by ancient people in a way to show the seasons. Also, many are shaped like phallus (the plural of which I am not certain of).
I am calling this site the Muisca Observatory as that is what I knew it as when I visited. The site is also referred to as El Infiernito or Little Hell. A nickname given by the Spanish for this site of pagan worship. It now seems to commonly be called Penis Park for obvious reasons.
Archaeology was not the primary reason I visited Colombia. I was surprised to learn there are great sites other than the Lost City, which was too long of a trek for me. The works of the ancient people were a highlight of my trip. I saw the carvings of San Agustin, and wrote about them here. I also saw this small but interesting site outside of Villa de Leyva.
Again I am faced with a dating dilemma. What I was told at the site, learned my research at the time, and recorded in my journal is 2000BCE as the date this observatory was built. As I am verifying my spelling and revisiting research I am finding articles making it much newer. Some sites are claiming as new as 900 CE now. The Muisca people lived in the area since at least 5000 BCE they have dated skeletons to that time frame.
The specifics of the people and the uses of this site are mysterious. They may align with equinoxes and other astronomical events but there was not enough discovered to be certain. Typically phalluses are said to be for fertility temples or ceremonies so that was what was determined here. I visited a modern park in South Korea that was full of penises just for fun. I suppose that could be the reason here too? It would be a lot of work to carve and stand the stones just for amusement. It is probably a fertility offering/temple.
Nearby Sites
Nearby you can visit a fossil of a kronosaurus an ancient sea creature on display. There are abundant sea fossils in this area. The nearby Convent Santo Ecce Homo has an alter made out of fossils.
Logistics
Visiting Villa de Leyva is easy. It is a 3 hour bus ride from Bogota. The village is a popular weekend spot for people in the Capital. I enjoyed visiting during the week when it was less crowded.
The sites were just outside of town. I hired a taxi to take me to the Observatory as well as the fossil site and the Convent Santo Ecce Homo. Taxis were very familiar with people wanting to go to these places and had a rate inclusive of the three and waiting time.