Downtown (El Centro) is the actual backbone of Cancún. What it lacks in history, it makes up for being a true melting pot — an exciting mix of the old traditional Mexico and an ultra-modern urban sprawl. Avenida Tulum, the main street, passing through the heart of the city, is easy to reach by public transport. The street is lined with shops, cafés, bars, and restaurants. Be sure to stop by Parque de las Palapas, on the market square, where locals come to chat and watch the entertainment provided by various local groups. The lively atmosphere and the sound of Mexican music are infectious, and any worries will quickly be postponed to "mañana." Browse around the artisan stalls and try some of the local sweet delicacies or visit the "Hippie Market" around the corner. In the evenings, the place to be is Avenida Yaxchillan with its lively restaurants and bars, popular with locals and tourists alike.

As you explore the nooks and crannies of the Old Town, it is worth taking a moment to step into the peaceful interior of this Gothic church. The building was completed at the start of the 17th century for the order of the Poor Clares. The Hejnał, a trumpet hymn to the Virgin Mary, is played from the old church tower at 12pm, 3pm and 6pm.

The lively and friendly atmosphere of Parque de las Palapas is worth a visit, especially on the weekend evenings. Watch a local performance on the open-air stage, browse around the artisan stalls, visit one of the bars and cafés around the park, or just come here to observe and soak in the atmosphere. Just across the adjacent car park, next to the church, you'll find the so-called "Hippie Park" offering hand-made jewelry, lamps, and tie-dyed clothing.

Unlike most aquariums, at the Interactive Aquarium of Cancún, you'll get a chance to get up close to sea creatures and even interact with some of them. Here, you can touch starfish and sea urchins, swim with dolphins, or watch them put on a show. There are over 140 species on display here and the Aquarium is open 365 days a year.