Day 1: The Strip in 24 Hours
South Strip & Mandalay Bay
Start at the Welcome to Fabulous Las Vegas sign on Las Vegas Boulevard. Arrive before 9am to skip the line for photos. Walk north along the Strip to Mandalay Bay's Shark Reef Aquarium ($29) or head straight to the Bellagio to see the stunning botanical conservatory (free, changes seasonally). Breakfast at Mon Ami Gabi at Paris Las Vegas, where French crepes ($14) on the Strip-side patio with Bellagio fountain views are the best morning in Vegas.
Casino Crawl & Free Shows
Walk the mega-resorts: the Venetian's Grand Canal Shoppes (indoor gondola rides, $34), Caesars Palace's Forum Shops with living statues, and the LINQ Promenade to the High Roller observation wheel ($25 daytime, $37 night). The Bellagio fountain shows run every 15 minutes from noon (free). Lunch at the Cosmopolitan's Secret Pizza. Follow the hallway on the 3rd floor past the pizzeria signs for $6 slices that rival New York.
Fremont Street & Downtown
Take the Deuce bus ($8 all-day pass) or Uber to Fremont Street Experience downtown, a 5-block pedestrian mall covered by a massive LED canopy with light shows every hour. This is old-school Vegas: neon signs, cheaper drinks, and friendlier tables. Dinner at Carson Kitchen in a converted motel ($16–24 plates). Grab a $3 beer from one of the Fremont bars. Walk to the Arts District on Main Street for cocktails at Velveteen Rabbit or ReBar.