Some of the most famous historical sites would be just another old house or pile of rubble if you didn't have any background information about their significance. Tourists have always had options for educating themselves about what they're looking at. They can read relevant books beforehand, they can hire a tour guide, or, if everyone in the group has the patience, they can take the time to read every plaque and sign on the premises.

Now, many programmers are also offering tourists the option to learn about these sites via their smartphones. While many of the world's significant historical locations have some sort of interactive app connected to them, the seven we picked below are among the most innovative and impressive.







The first London hospital started in the 12th century and was run by monks, not doctors. The morality of patients was assessed before they were admitted, and people with contagious diseases were omitted.

This tour, which starts at Lincoln's Inn Fields in London and ends at the Wellcome Collection, explains the history of medical developments that occurred between this point and today. At 10 stops along the way, you'll listen to audio clips about the history of anesthetics, amputation, neurology, women and medicine, and some of London's historic medical centers. The Wellcome Collection, which "explores the connections between medicine, life and art in the past, present and future" collaborated on the creation of this app, and their knowledge of this niche subject is apparent in the result.







The author of this app, Jonathan Eig, is a former Wall Street Journal reporter and the author of Get Capone. In other words, he is not only knowledgeable about the subject, but an engaging writer. This app plots the nearby locations of 1920s gangster activity like the St. Valentine's Day Massacre, and gives you the detailed back stories.

3. Library of Congress Virtual Tour







The Library of Congress is impressive, but it also invites questions like, "Why is that statue holding a sailboat?"

This free app gives the basic historical rundown of notable rooms of the Library in text, audio, and video. It allows you to scroll through pictures with headlines that often note the answers to your more specific curiosities. For instance, "That statue represents Commerce. She's holding a model of a Yankee schooner."

4. Boston Freedom Trail App







For each of the 16 marked historical sites along Boston's Freedom Trail, this app has a written explanation as well as professional-quality audio and HD video component. Knowing some history about Colonial Revolutionary Boston really enriches the tour, and at $2.99 this app is much more affordable than a guide. There's also a map feature, which is less important than the commentary because the entire trail follows a physical thick red line.







The 20th century had the O.J. Simpson trial; the 19th century had the trial of Professor John Webster. In 1849, Webster was accused of killing Dr. George Parkman, one of the richest men in Boston. Pieces of Parkman's body were found in and under the Harvard Medical College. The country was captivated by the gruesome crime and it's high profile victim. PBS made a documentary on the investigation decades later that was called Murder at Harvard. This app is a companion to the film.

The app artfully directs you to eight Boston locations and reveals a relevant bit of the story at each one. Instead of directing you to locations you might notice on a walk, videos lead you not only into The Etherdome of Massachusetts General Hospital, for instance, but to a specific railing where you can see a specific log that used to hold up the Harvard Medical College.

Taking this tour is like being inside of a documentary, which is part of what led to it being the first app accepted as an entry to the Boston International Film Festival this year. It won the Indie Spec New Media Award.







Hollywood's hometown newspaper has archives of information on it's famous neighbors. The Los Angeles Times puts it to use in this app, which maps the locations of more than 2,000 stars' homes on Hollywood's Walk of Fame. Search by celebrity name, by block, by type or by GPS location. If you're planning a day of celeb star spotting, you can customize a tour with your favorite stars. The app even has an augmented reality option that will point you in the direction of a particular celeb's star.







Want to see if the road you are standing on existed 100 years ago? The "time travel" aspect of this app is the ability to toggle between an antique map from 1862 and today's map. You can do this no matter how far zoomed-in you are on the map to see how your surroundings have changed. There are also about 750 points of interest identified on the map. Many of them include historical photos and audio explanations. Because they are provided by the British guild of registered tour guides, these explanations tend to sound exactly like what you would expect on a guided tour.

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