Caves often hold ancient treasures such as paleolithic paintings, extinct animal fossils, and silent-movie DVD box sets. Survey long forgotten relics with today's Groupon: for $38, you get a three-hour Wet and Wild Cave Adventure tour at Horne Lake Caverns in Qualicum Beach (a $77.28 value, including HST). Tours leave daily at 1:30 p.m. by reservation only.

Horne Lake Caverns' three-hour Wet and Wild Cave Adventure tour embraces the rainy season’s pluvial bounty and allows spelunkers of all ages and abilities to embark upon educational and exhilarating sojourns. Helmed by a savvy guide, subterranean explorers wend through vast marble passages while gawking at crystal caverns and making small talk with the goblins that call them home. Ascend a waterfall, take photos of an underground river, and treat eyes to unearthly vistas. Grotto-travellers keep arms and ears folded close to their bodies while squeezing through narrow ceiling galleries festooned with a century's worth of bat-painted frescoes. Underground ushers advise participants to bring along a full change of clothes to don post-tour, and explorers should be prepared to wiggle through tight spaces, partake in short climbs, and engage in cave scrambling. As Horne Lake Caverns supplies tour takers with all the necessary equipment, adventurers can leave their miner’s lamps and inflatable stalactites at home.