Exploring the history and wonders of D.C.

LYSA ALLMAN-BALDWIN | 6/12/2013, 6:21 p.m.

In the first part of our travel series on Washington, D.C., we learned about the city's founding and early African-American history. Now, we're getting out and about to explore the myriad of exciting, educational and impressive sites and attractions the city has to offer.

The first thing that almost everyone, resident or visitor, will tell you about visiting D.C. is that you can find lots--and by that I mean close to 100--free and almost-free things to do in and around town, which makes it a very family-affordable vacation for people of all income levels. However, visitors should note that some attractions require timed entry tickets due to the large number of visitors.

There are so many wonderful things to do, in fact, that I couldn't possibly do them all justice here. So I'll start with many of the attractions our family visited during our vacation here last summer.

If you come to D.C. by bus or train, your first tourist attraction will be front and center as you arrive at Union Station. Opened in 1988, Union Station is a true D.C. hub--an estimated 90,000 visitors traverse it daily. In addition to accessing the facility for transportation purposes (car rental services are available here, and it is also Amtrak's corporate headquarters), both visitors and residents alike flock here to the over 100 specialty shops, 35 dining establishments and a wide range of other services.

It is impossible to visit D.C. without first understanding its biggest tourist attraction--the Smithsonian Institution. Many people think it is just one place--"The Smithsonian"--but it is actually the world's largest museum and research complex, encompassing 19 museums and galleries, nine research facilities and the National Zoological Park. Among these are the African American History and Culture Museum, the Castle, the Postal Museum, the Natural History Museum, the African Art Museum and the Freer Gallery of Art, just to name a few.

One of our favorite attractions was the National Air and Space Museum (if your kids saw "Night at the Museum 2: Battle of the Smithsonian," they will be particularly enthralled), home to the largest collection of historic air and spacecraft in the world. The exhibits and artifacts are amazing, offering a great deal for all ages on the history, science and influence of aviation, astronomy and space flight.

If mystery and intrigue float your boat, you will love the International Spy Museum. We could have literally spent all day in there, exploring the downright fascinating world of espionage presented via spectacular state-of-the-art interactive exhibits, both permanent and temporary.

From spy-related artifacts to historic photographs, audio and video surveillance presentations--including the personal stories of spies from around the world, an air vent you can crawl through to "spy" on a top-secret encounter and more--it's no wonder that the museum is billed as "the first and only public museum in the United States solely dedicated to espionage and the only one in the world to provide a global perspective on this all-but-invisible profession." A visit here is an absolute must--and they even have separate spy adventures for older children that give them the opportunity to engage in their own clandestine espionagic (I just made up that word) escapades.