Mandalay Bay and Bally’s sit at opposite ends of the Las Vegas Boulevard "Strip" corridor. Here are the practical options.
Distance: ~1.6 miles (2.6 km).
Time: 35–40 minutes at a brisk pace.
Experience: Passes through multiple casino resort frontages (Luxor, Excalibur, NY-NY, Park MGM, Bellagio, Caesars, etc.). Pleasant in cool weather; grueling in summer heat.
Distance: ~2 miles (3.2 km) via Las Vegas Blvd or I-15 frontage.
Time: 5–10 minutes (longer during peak congestion).
Cost: Typically $12–$20 base fare; surges can double it.
Route: Board the southbound Deuce at the Mandalay Bay stop (Las Vegas Blvd @ Mandalay Bay Rd). Ride ~8 stops to "Bally's / Paris Las Vegas".
Time: 10–15 minutes.
Fare: $6 (2-hour pass) or $8 (24-hour pass) exact change or app.
Frequency: Every 15–20 minutes.
The Las Vegas Monorail runs behind the east-side casinos (MGM Grand to Sahara). It does not serve Mandalay Bay or Bally’s directly; you’d need a tram/shuttle connection at each end—usually slower than the Deuce.