Most folks simply frequent the bar at their hotel, or stick around after dinner at one of the local restaurants. There are several bars along Calle Sur fronting the lake just over the bridge as you enter Flores. Of these, AAdictos is one of the liveliest. For a view of the lake and a happening party scene, you can head to Bar Raices, at the far western end of Calle Sur. Another good option, near the center of the island, is Las Puertas, which has been playing a mix of house and chill dance tunes in a hip little space, and sometimes has live music; it's located at the corner of Calle Centroamérica and Avenida Santa Ana.
Finally, if you're in a gambling mood, you can head to the Maya Princess (tel. 502/7924-8764), located on 2a Calle 7-00, Zona 1, in Santa Elena. This place has a wide range of electronic gaming machines and nightly bingo, and a swank, Las Vegas-like ambience.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.