El Cortez in Las Vegas turns 75. (Makes 50-year-old Caesars seem young)

It’s party time for yet another long-standing Las Vegas hotel. Following Caesars Palace’s 50^th anniversary this summer, the El Cortez is marking an even-bigger milestone – 75 years – this week.

Built for just $245,000, the El Cortez filled a full city block when it opened on Nov. 7, 1941. Four years later, the Mob sank its claws into the property when Bugsy Siegel and three other gangsters bought it. The hotel-casino has been family-owned since 1963, and its newest addition remembers the past with a 24/7 restaurant named Siegel’s 1941.

The hotel, which has about 350 rooms, held an anniversary party with cake and Champagne on Nov. 1.

The front of the hotel — in the now-booming Fremont East Entertainment District — has changed little over the years, Indoors, though, it’s a mix of old and new. Slot machines still accept coins, and the second-floor “vintage� rooms, which overlook Fremont Street, look much the same as they did in the ’40s, but with modern amenities. The hotel’s relatively new Cabana Suites offer modern rooms in a boutique setting.

The Mob extended its reach on Dec. 26, 1946, when Siegel opened the Flamingo, a sprawling, 40-acre resort along what’s now the Strip. It cost $6 million to build.

The original low-rise hotel with its pink façade is long gone. The modern-day tower is wrapped with giant photos of headliners Donny and Marie Osmond.

Out back, two large pools, including one for adults only, are found not far from the resort’s Wildlife Habitat. Its critters include, of course, pink flamingos, Chilean ones, to be specific.

In a quiet garden many visitors overlook, there’s a memorial to Siegel on the site of the original hotel, which became known as the “Bugsy Building.� The marker points out the building included a secret escape route built specifically for Siegel. It housed a ladder hidden in a closet that led to an underground garage, where a getaway car awaited.

The elaborate plans were for naught. Less than six months after the Flamingo’s gala opening, Siegel was gunned down in Beverly Hills. No one was ever charged with the murder.

A reported $6 million was also spent on the Fremont Hotel, marking its 60^th anniversary this year. When it opened along Fremont Street in 1956, the high-rise became Nevada’s tallest building.

Now beside the canopy of the Fremont Street Experience, the hotel is one of a few downtown properties that cater to visitors from Hawaii. So many Hawaiians visit Las Vegas that they refer to as “the ninth island.�

Probably Nevada’s best-known hotel, Caesars Palace is the youngest of the hotels observing anniversaries this year. Caesars turned 50 this summer, having welcomed its first guests on Aug. 5, 1966.

The popular resort celebrated with two nights of star-studded festivities. A Saturday evening gala on Aug. 6 featured Tony Bennett, Wayne Newton, Donny and Marie Osmond, the Righteous Brothers and others.

Caesars visitors can take a self-guided walking tour, during which various historic events, such as Evel Knievel’s failed attempt to jump the hotel’s fountains, are remembered.