If Las Vegas is a city built on vice, its bricklayers are conventioneers. Each year, 4.5 million lanyard-wearing, welcome packet–toting businessmen descend upon Sin City for no fewer than 18,000 conventions. (World of Concrete Annual Meeting, anyone?) So between marathon panel discussions, you lose $500 at the craps table, drop another $100 on a rib eye at Tom Colicchio's, and slip – how much was it again? – into G-strings at the Spearmint Rhino. Here's the antidote: three soul-restoring adventures waiting just outside the city. And none of them requires a lanyard or a fistful of singles.
Miles from the Strip: 30
A half-hour drive southeast, in the austere beauty of the Mojave Desert, is the 35-mile River Mountains Loop Trail, a paved bikeway that connects the town of Boulder City with Lake Las Vegas, the Hoover Dam, and the Lake Mead National Recreation Area. The jagged peaks and scorched valleys of the River Mountains are home to tortoises, bighorn sheep, and desert foxes, as well as bobcats and mountain lions. Rent a mountain bike at All Mountain Cyclery, in Boulder City [$55 for a half day; allmountaincyclery.com], and get on the trail at the Bootleg Canyon Park access point. Be sure to explore the 3.7-mile Historic Railroad Tunnel Trail, which cuts off to the east after a few miles and takes you through the five railroad tunnels, each 300 feet long, that supported construction of the Hoover Dam in the early 1930s.
Miles from the Strip: 35
Depending on what floor your hotel room is on, you might be able to spot Mount Charleston rising 11,918 feet to the northwest. The peak, the highest in southern Nevada, sits in the Spring Mountains National Recreation Area, where the temperature is typically 25 degrees cooler than Las Vegas. The area offers 51 miles of hiking trails through rocky canyons and bristlecone pine forests. Beginners might try the two-hour, three-mile Mummy Springs Trail, which extends off the North Loop. Others should go for the six-hour, 8.3-mile South Loop. The path climbs steeply from its start off the Cathedral Rock trail before wandering through open meadows. The last half-mile is an arduous – but rewarding – push to the summit.
Miles from the Strip: 20
Just west of Las Vegas, the Red Rock Canyon National Conservation Area offers rock climbing on massive, striated salmon-and-ivory sandstone formations, the tallest of which rises 7,000 feet. Hire a guide through the American Alpine Institute, which runs climbing trips from $325 a day [aai.cc]. After getting picked up at your hotel and outfitted with shoes, helmet, and harness, you'll be led up tricky ascents with names like Johnny Vegas and Cat in the Hat. Scramble above 700 feet for a view over the limestone Blue Diamond Hill and back to the glittering casinos.