Downtown Las Vegas is where the city actually started, decades before the Strip existed. The hub is Fremont Street, the five-block pedestrian-only stretch covered by an enormous LED canopy that runs hourly light shows. The casinos here are smaller, older, and several of them — the Golden Nugget, the El Cortez, the Plaza — have been operating in some form since the 1940s or 1950s.
The vibe is louder, cheaper, and more bachelorette-party than the Strip. Cocktails come in plastic yard glasses, table-game minimums are lower, zip-liners scream overhead under the canopy, and street performers vie for change. East of the canopy, around Sixth Street, the Fremont East Entertainment District is the better grown-up zone, with cocktail bars, breweries, and the Container Park.
This is also where the major non-casino sights cluster: the Mob Museum, the Neon Museum, the Smith Center, and the AREA15 / Arts District are all a short ride from downtown. Stay at a Fremont hotel for one of the cheapest comparable-quality Vegas experiences — you trade Strip glamour for budget rates and quick access to the city's more interesting cultural offerings.