New York, NY
With its swirling multi-story ramp, the Guggenheim is one of the most iconic buildings in New York City – no small feat – and possibly the nation. One of Frank Lloyd Wright's most notable projects, it now draws both art and architecture lovers on a daily basis.
How to visit: The museum is open every day but Thursday, and those looking to visit on the cheap should take advantage of a "Pay What You Wish" program on Saturday evenings. There are daily tours that are free with admission.
Washington is full of grand buildings; fittingly, one of the grandest is the U.S. Capitol Building. A prime example of neoclassical architecture that draws from ancient Greece and Rome, it has more than 600 rooms. The cast-iron dome, painted to look like stone, took 11 years to build.
How to visit: Visitors can book 45-minute guided tours in advance online. Separate passes are required to visit the House and Senate galleries – contact your representative or senator to obtain one.
DENVER INTERNATIONAL AIRPORT
Most airports are high on function and low on design, but nothing could be further from the truth in Denver. The roof of Denver International Airport is made of an innovative fiberglass fabric that rises and falls in tent-like peaks meant to evoke the Rocky Mountains, pioneer wagons, and Native American teepees. The building is eco-friendly, too, with features such as its own solar farm.
How to visit: You don't need a plane ticket to marvel at architecture of the famous Jeppesen Terminal, which includes several shops and restaurants as well as check-in and baggage claim.
Whether you call it the Willis Tower or stick with its old moniker, the Sears Tower, no one can deny this building's place in American architectural history. At 110 stories, it was the tallest building in the world for a quarter-century after it was completed in 1973. It's even built to sway up to 3 feet from its true center during those notoriously windy Chicago winters.
How to visit: Book a visit to the Skydeck on the building's 103rd floor for a truly unparalleled view. Nerves of steel? Step onto a glass ledge that lets them "float" 1,353 feet above the ground.
WALT DISNEY CONCERT HALL
Los Angeles, CA
The stunning Walt Disney Concert Hall didn't open until 2003, but it has quickly become a must-see for architecture buffs. Designed by Frank Gehry, it features a curving stainless steel exterior reminiscent of wind-blown sails. The equally grand interior, home to the L.A. Philharmonic, seats more than 2,200.
Thomas Jefferson's talents extended to architecture, and a visit to his graceful, neoclassical Virginia estate proves it. He designed (and redesigned) the home over 40 years, and it wasn't complete until 1809, the final year of his presidency. Monticello's most famous element – its west portico, with a half-moon window and doric columns – has been enshrined on the back of the nickel.
How to visit: The estate is open daily for visitors, who receive a discount for booking tickets online. A house tour, slavery-focused tour, and grounds tour are included with admission.
ROCK AND ROLL HALL OF FAME
The glass pyramids that make up part of the Rock and Roll Hall of Fame have made this I.M. Pei building one of Cleveland's most recognizable landmarks. Other notable features include a theater that's cantilevered over Lake Erie, a circular performance drum, and a tall, angular tower.
How to visit: The museum is open daily for both music lovers and architecture buffs alike. Special events including films and concerts are also held throughout the year.
OLD STATE CAPITOL
Baton Rouge, LA
A mashup of a Gothic cathedral and a medieval castle, Louisiana's Old State Capitol is simply begging for a moat, a knight, and a damsel in distress. Highlights include several turrets, an imposing spiral staircase, and a dazzling stained-glass dome.
How to visit: Today, the building is a museum that's open to the public. Admission is free, and free audio guides are available.
Eureka Springs, AR
Tucked away in the Ozarks, the Prairie-style Thorncrown Chapel is one of the most-lauded buildings of the 20th Century. It's easy for visitors to see why: Soaring criss cross beams and massive glass windows invite the outside in, flooding the structure with light and making nature the star.
How to visit: Visitors are welcome most days March through December, and Sunday worship services are open to the public.
This is as far as you can get from library stereotypes like dark stacks of books and dim reading rooms. Instead, the postmodern Central Library is flooded with light, defined by its diamond-shaped glass and steel façade. Inside, a "books spiral" displays the entire nonfiction section without any need for separate rooms.
How to visit: The library is open to the public every day, but visitors interested in hearing more about the architecture and design can take self-guided cell phone tours of the building.
WASHINGTON NATIONAL CATHEDRAL
The U.S. has its fair share of stunning churches, but the neo-Gothic Washington National Cathedral might be the most interesting. The sixth-largest cathedral in the world, it took 83 years to build and includes surprises like a limestone Darth Vader grotesque and a lunar rock embedded in a space-themed stained-glass window.
How to visit: Sightseeing hours, which require an admission fee, are offered every day and include a guided tour. Worship services are free and open to the public.
La Jolla, CA
The main library building at University of California San Diego is distinctive – and polarizing – to say the least. A fusion of glass and concrete that seems to hover like a UFO, it's one of the best examples of Brutalist architecture in the U.S.
How to visit: The library is open to the public much of the year. It offers art- and architecture-focused walk-in tours for the public at certain times. Self-guided tours are also available.
If you feel like you're on a French estate while visiting North Carolina's Biltmore House, it's for good reason: It's meant to evoke the feeling of a grand chateau. The largest private home in America, it was built by Richard Morris Hunt, with gardens designed by Frederick Law Olmstead. Highlights include a grand cantilevered staircase, stone gargoyles and grotesques, and a banquet hall with 70-foot ceilings.
How to visit: Daytime visits, though pricey, include a lot: a self-guided tour of Biltmore House, access to the surrounding gardens, a wine tasting, and more. Audio guides and guided tours are available for an additional fee.
J. PAUL GETTY CENTER
Los Angeles, CA
The iconic Getty Center occupies an enviable perch in the Santa Monica Mountains, giving visitors a dazzling view of L.A. and the ocean beyond. But this art museum's modernist buildings are equally stunning, featuring 1.2 million square feet of travertine imported from Italy as well as massive glass walls, sunken gardens, water features, and terraces.
How to visit: Admission is free (though there is a parking fee), and there are daily tours focusing on the center's architecture.
Mill Run, PA
Architecture lovers won't regret the hour-long pilgrimage from Pittsburgh into the Pennsylvania countryside to see Fallingwater, widely considered Frank Lloyd Wright's best work – and among the best-designed homes of all time. Cantilevered dramatically over a waterfall, the home is meant to blend into the gorgeous landscape that surrounds it.
How to visit: Guided tours are available most days, but visitors must book in advance online.
EMPIRE STATE BUILDING
New York, NY
The Empire State Building was the world's tallest for more than 40 years after its completion in 1931, topped only once the World Trade Center was completed in 1972. But the Art Deco structure remains one of New York's most iconic landmark, with its famous 16-million-color tower lights that change color most days to recognize different holidays and causes.
How to visit: The building is open daily for visitors, who can choose whether to ascend to the main open-air observation deck, on the 86th floor, or add the top deck on the 102nd floor. Visitors can also poke around the lobby and visit two exhibits, including one on the building's construction.
PHILADELPHIA CITY HALL
This 700-room National Historic Landmark is the largest municipal building in the nation, and is even larger than the U.S. Capitol. Its Second Empire façade was influenced by Parisian palaces and features plenty of opulent flourishes like elaborate dormers and columns. One of the most famous highlights: A massive 37-foot bronze statue of William Penn that towers above the building.
HOTEL DEL CORONADO
Though most people associate Queen Anne architecture with rambling Victorian homes, the splendid Hotel del Coronado near San Diego is a great example on a much larger scale. Opened in 1888, it features grand red-roofed turrets and white verandas that overlook the Pacific.
How to visit: Though visitors can poke around the lobby and other public areas, those who want a more in-depth experience can join a history tour that covers the building's architecture.
U.S. AIR FORCE ACADEMY CADET CHAPEL
Colorado Springs, CO
It's not hard to see why the Cadet Chapel, made of aluminum, glass, and steel, is one of Colorado's most-visited man-made tourist attractions. Its ultra-modern 150-foot triangular spires dramatically pierce the sky. Inside, light floods through the stained glass below the awe-inspiring ceiling.
How to visit: Visitors are welcome during business hours Monday through Saturday, and on Sunday afternoons. A nearby visitors' center provides more information on cadet life and the history of the U.S. Air Force Academy.
Opened in 1908, Union Station is among the grandest of the nation's many grand train stations. Its Beaux Arts façade blends seamlessly with Washington's many elegant buildings, and it's hard to detect that, the building had deteriorated so much by the early '80s that Congress had to step in to force a restoration. Today, the building's signature element is its dramatic vaulted ceiling, replete with gold-leaf coffers.
How to visit: Browse the station's shops or grab a bite at its sit-down restaurants and food court during normal business hours. The station is also included on the itinerary of many third-party D.C. tour companies.