Recent specific threats from Islamist propaganda broadcasts indicate Sin City may become a bomb target. It’s a deadly serious situation, but it brings up a local joke that has been around since the Cold War. Here it is:

If you’re on Las Vegas Boulevard and there’s a warning about a bomb attack, immediately run into a luxury resort on The Strip. Hide under any slot machine in the casino, because none of them will ever be hit.

Seriously, in Las Vegas and at all other world travel destinations you'll visit, keep constantly alert to possible terror attacks where large numbers of people assemble. Have an alternative plan when immediate danger is indicated, and be prepared to find safety in an emergency.

They’ve all performed there. Callas, Caruso, Horowitz, Rachmaninoff, Billie Holiday, Sinatra, the Beatles, Pavarotti, Benny Goodman, Miles Davis, What better way to celebrate the birthday of the famous entertainment location than with entertainment?

Current shows feature the New England Symphonic Ensemble, New York Youth Symphony, the MET orchestra, city-wide exploration of West Side Story, Moscow Virtuosi Chamber Orehestra and commissioning of 125 new musical works. carnegiehall.org/125

Many of the world's historic domes have been around a thousand years, a testament to their design and construction. Here are three European domes that would make a great destination for senior travelers:

Pantheon: Rome, Italy. Built in 126 AD, it remains the world's largest non-reinforced concrete dome. It sits in the heart of Rome and is a spectacular site to visit. Inside, the space is cathedral-like. The distance to the top of the roof opening (called the "oculus") is the same as the diameter of the circular floor, both 142 feet.

Your travel4seniors.com editor recently enjoyed an African safari at the expansive game reserve in Narok County, Kenya. Along with lions, leopards, elephants and rhinos, this lively little guy seemed the most friendly.