El Castillo, also known as the Temple of Kukulcán, is the iconic centerpiece of the ancient Mayan city of Chichén Itzá. This step pyramid is a marvel of Mesoamerican architecture, showcasing the Maya's advanced understanding of mathematics, astronomy, and engineering. Accessibility can be challenging for those with mobility issues due to uneven terrain and steps. Both solo and guided visits are rewarding, with guided tours offering deeper insights into the site's history and significance. The best time to visit is during the dry season (December to April) to avoid rain and humidity. Expect to spend approximately 2-4 hours exploring the site. Entry fees are around $30 USD. Be prepared for large crowds, especially during peak season, and bring sunscreen, a hat, and plenty of water.