In the heart of Oman lies Nizwa, a city once considered the country’s capital and a hub of learning and trade. Its iconic round fort, built in the 17th century, remains one of Oman’s most visited landmarks.

Kirkwall, the vibrant capital of the Orkney Islands, Scotland, is a place where history and culture intertwine with stunning natural landscapes. Founded by Norse settlers over a thousand years ago, Kirkwall is steeped in Viking heritage, with its centerpiece, the magnificent St. Magnus Cathedral, standing as a testament to the town’s medieval past.

Ol Doinyo Lengai, often called the "Mountain of God," is an active volcano located in northern Tanzania and is a must-visit for adventurous travelers. Towering over the Great Rift Valley, this majestic peak is unique due to its lava composition. Unlike most volcanoes that produce molten lava, Ol Doinyo Lengai emits natrocarbonatite lava, which is unusually cool and flows like water. This rare phenomenon makes it one of the most intriguing volcanic landscapes on Earth.

Key Largo, the northernmost of the Florida Keys, is renowned for its pristine natural beauty and vibrant marine life. As part of the Florida Keys archipelago, Key Largo is a gateway to the spectacular underwater world of the John Pennekamp Coral Reef State Park, the first underwater park in the U.S. Here, visitors can explore vibrant coral reefs through snorkeling and scuba diving, or take a glass-bottom boat tour to marvel at the colorful marine ecosystems without getting wet.

Whether you are in D.C. on business or vacation, you'll find that it's a fascinating city that is full of history, art, theatre, and dramatic monuments.