Lagoa da Rondinha is a freshwater lagoon located on the Litoral Norte of Rio Grande do Sul, straddling the municipal boundary between Cidreira and Balneário Pinhal. The lagoon covers approximately 8.73 km² and reaches a maximum depth of around 3.8 meters. Access is via the ERS-040 highway, with the main infrastructure concentrated in the Figueirinhas district of Balneário Pinhal.

The water is notably clear with a bluish tone, and the lagoon is suitable for swimming as well as water sports. Paddlers will find calm, sheltered water well suited to kayaking and stand-up paddleboarding. Jet-ski use is common on the lagoon, so paddlers should be aware of motorized craft sharing the water. A 100-meter pier (trapiche) serves as an anchorage point for boats and provides a reference landmark on the water. The surrounding landscape includes sand dunes and native vegetation.

The lagoon is designated for recreational use by bathers and for sport activities. During the summer season, the local municipality installs a lifeguard station at the site, indicating that the area sees significant visitor traffic in the warmer months. The water quality is consistently clean and clear.

For paddlers planning a trip, the late afternoon light creates shifting reflections across the water's surface. The area around the lagoon is open and flat, with the dune and native forest backdrop providing visual interest. The overall character of the paddling experience is calm and unhurried, with no significant current or tidal influence.

The site has basic visitor infrastructure in place, and its location directly off the ERS-040 makes access straightforward for those traveling along the northern coast. Given the lagoon's relatively modest depth and calm conditions, it is appropriate for paddlers of varying experience levels.