Well where to begin... There's a lot of history here with this family since Ponce is the home to Don Q rum (the preferred rum of Puertoriqueños throughout the island - and not Bacardi like most would assume), and this castle once housed the Serralles family - owners and makers of Don Q. It's commonly referred to as the Castle the Rum built... and when you're there, you'll see why.
It was built just south of El Vigia (which can also be seen from most of the gardens on the property), and because of it's location can be seen in nearly every part of Ponce. The Castle itself is absolutely beautiful, and extremely decadent for it's creation in 1930. So much so, that it took 4 years to complete the Spanish & Morrocan influenced four-floored mansion with it's sculptures, library, terraces, hand-carved furniture, art, indoor patios, fountains, pool, and surrounding gardens - including a butterfly garden. Think of it in terms of a Puerto Rican version of the Great Gatsby/prohibition era... Very extravagant, even criminal chic. Keep in mind again, that the Serralles family was the richest family in Ponce, and with that type of power came even greater amounts of money and violence.
You can schedule your tour in advance (which I'd recommend), or walk up to the site itself at the gate and coordinate a tour within the office. I'd recommend buying a combo ticket so you can visit the Serralles Castle and El Vigio (it's literally less than 200 feet away I believe... so why not do both since you're there?!). The tour itself can depend on which tour guide you have - but having been a few times before I can say that most are amazing and very informative, I've only had one that was ehhh and that's because I felt a little rushed with my friends going through the house. I went on the tour with a young man who was amazing - although I sadly forgot his name by the time I made it to my car.
You'll enter their movie room for a brief 15-20 minute video providing a general understanding of the house, the family, and it's historical significance... and then you're off to explore the house with your guide. It's well kept and I've taken friends and family of all ages who truly enjoyed it. If you get the opportunity to go during a clear day - I'd recommend it so you can have a clearer view once you enter the gardens and pool area. For this last trip, I went one day prior to the tropical storm passing through Ponce so it was unusually gray, and the shots I took outside don't really do the view justice. Having been before, I can say that the views are amazing!
As a side note - if any of you are interested in having a special event there (usually a host for weddings), they offer those opportunities and experiences and since the staff is extremely personable they are more than willing to cater to your special event's needs. They also host an annual Halloween event that is AWESOME if you're in the area at that time too (you'd just need to purchase a ticket)!
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