Los Deltas occupies a 120-hectare wedge of coastal wetland between Palma's eastern suburbs and the Balearic Sea, protected since 1991 under regional conservation law. The reserve's name comes from the braided freshwater channels that once drained into Cala Gamba, though modern drainage has reduced the delta to seasonal pools and reed beds frequented by purple herons and glossy ibis. Jet ski operators launched guided routes through the reserve's offshore buffer zone in 2003, creating a tourism corridor that threads between no-wake buoys and maintains a 200-meter distance from nesting sites. The arrangement generates revenue for patrol boats and environmental monitoring, while giving riders access to water that remains off-limits to larger craft. The standard Palma de Mallorca Los Deltas jet ski tour departs from Club Náutico Cala Gamba, a mid-century sailing club with a concrete pier and fuel dock on the reserve's southern edge. Most routes follow the coastline southwest toward Palma's historic quarter, passing the modernist apartment blocks of Portixol and the stone breakwater at Es Molinar before reaching the Cathedral of Santa Maria, whose honey-coloured sandstone façade rises 44 meters above the waterline. Guides typically pause engines 150 meters offshore, allowing riders to photograph the Gothic rose window and the adjacent Almudaina Palace without violating the harbor's no-entry zone. The return leg cuts northeast across the bay's open water, where depth drops to 18 meters and chop builds in afternoon wind. Cala Gamba itself is a narrow crescent of coarse sand hemmed by tamarisk and Aleppo pine, popular with local families but undeveloped compared to Palma's resort beaches. The jet ski tours launch from the club's floating dock rather than the public beach, avoiding congestion and providing direct access to the reserve's seaward margin. Water temperature in the bay averages 14°C in February and peaks at 26°C in August, with visibility ranging from 8 to 15 meters depending on algae bloom and sediment runoff from winter storms. The route's shallow sections—rarely deeper than 4 meters near the delta channels—reveal patchy seagrass beds and occasional moon jellyfish drifting in the current. Conservation signage at the dock lists prohibited activities: no wake within 50 meters of shore, no approach to kayakers or paddleboarders, no deviation from marked lanes during April and May when shorebirds nest.