Castillo San Cristóbal, a formidable Spanish fortress in San Juan, Puerto Rico, offers a captivating journey through military history and stunning ocean views. While partially wheelchair accessible, many upper levels and tunnels require stairs, so comfortable shoes are essential for exploring its extensive grounds. Visitors can explore independently with informational plaques, but ranger-led talks or audio guides are highly recommended for deeper historical insights. The site is open year-round, with closures only on major holidays; however, visiting during hurricane season (June-November) might require checking weather forecasts. The approximate cost is around $10-15 for a combined ticket valid for seven days at both this site and El Morro, with children often entering free. A typical visit duration ranges from 1.5 to 3 hours. It's advisable to bring water, sunscreen, and a hat due to limited shade, and consider arriving early to avoid crowds and heat.