For $8, today's Groupon gets you two adult admissions to the Dallas Holocaust Museum (a $16 value). Admission includes the self-guided audio tour, available in English or Spanish.

The museum shares the lessons of the Holocaust with more than 40,000 students and 15,000 walk-in visitors every year, preserving the memory of the genocide’s victims while aiming to make a better future by imparting moral and ethical lessons. The museum’s permanent exhibit focuses on the behavior of three groups of bystanders on April 19, 1943. On that day, three young Belgians liberated a train bound for Auschwitz, the residents of the Warsaw Ghetto rose up in revolt, and British and American officials met in Bermuda but failed to take action against the Holocaust. This focus on a single day keeps the experience from overwhelming visitors while still encapsulating the horrific scale of the Shoah. The main exhibit puts weight behind the Albert Einstein quote at the museum’s entrance: “The world is too dangerous to live in—not because of the people who do evil, but because of the people who sit and let it happen.”

Along with its permanent exhibit, the Dallas Holocaust Museum also hosts special exhibits, such as the current The Ghosts of Auschwitz, wherein photographer Cole Thompson uses long exposures to haunt his pictures of the infamous concentration camp with ghostlike human forms.