Why do we love Christmas trees? Is it because the leaves are so unchanging, and the candles shine so brightly? Do we, like Charlie Brown, recall the true reason for the season when we contemplate a dressed-up evergreen? And why do we especially enjoy the incredibly tall ones? The lanky conifers with long, graceful branches seem particularly enchanting to us. But when it comes to our cherished spruces, only a few iconic, twinkling firs can captivate us with their annual display of yuletide splendor. To help spread the holiday cheer, we've rounded up some of the world's largest, oh-so-bright evergreens for your viewing pleasure. Prepare to be amazed at these tree titans and the Christmas spirit found in their home towns.Just in case you're wondering, the trees listed here are au naturel—comprised of real wood and pine needles. In other words, Brussels' wood-and-steel abstract tree and Rio de Janeiro's 542-ton floating tree, though magnificent, won't appear on this list. This year, on December 6th, the first family ushered in the holiday season by igniting the 30-foot National Tree in the White House's President's Park. Through the end of December, spectators can marvel at the Colorado Blue Spruce's 450 strings of LED lights and 120 star ornaments (all of which were engineered by General Electric). After catching sight of the magnificent tree, peruse the "Pathway of Peace"—a series of 56 miniature trees decorated with ornaments from America's states, territories, and the District of Columbia. By the way, if you missed the lighting ceremony, you can watch it online here.From the "Lucy" lights (12,000 white, red, and blue LED lights that glimmer along the Bahnhofstrasse shopping avenue) to the cheery Christmas markets, Zürich sparkles at Christmastime. But nothing gleams brighter than its 50-foot Christmas tree. With typical Swiss elegance, the spruce tree—which was chopped down from the nearby Uetliberg Mountain—glitters with more than 7,000 Swarovski crystal ornaments. You'll find the glorious tree perched inside the Zürich Hauptbahnoff Railway Station, which also plays host to Europe's largest indoor Christmas market. Here, you'll find 150 stalls selling tantalizing Swiss snacks and hand-crafted holiday gifts.Every year since 1947, the people of Oslo have gifted London with an awe-inspiring Christmas tree. This annual present symbolizes Norway's thankfulness to Great Britain for its support during World War II, and for many Londoners, the annual tree lighting kicks off the holiday season. Hundreds of lights are strung in typical Norwegian fashion (vertically draping from top to bottom) in a simple, but visually pleasing display. You'll find the statuesque Norwegian spruce rising majestically from London's Trafalgar Square, surrounded by the National Gallery and Nelson's Column, among other London landmarks.In a holiday tradition that stems back to 1937, Sydneysiders showcase their Christmas spirit with bright, twinkling lights at Martin Place. The source of the city's illumination is an enormous Christmas tree that rises 69 feet into the air and is speckled with a whopping 59,000 lights. To cap off the fluorescently-lit fir, a five-foot star is placed on top. The annual tree lighting is met with much fanfare—concerts, dancing, fireworks, and more. This Aussie city opts for brilliant multi-colored ornaments rather than the classic crystal other cities like Zürich or Paris display.Christmastime is one of the busiest times of the year, so if you want to knock two things off your to-do list at once—marveling at a spectacularly decorated tree and holiday gift shopping—head to the Galeries Lafayette department store along Boulevard Haussmann in central Paris. One of the city's most elegant trees hangs inside the gorgeous Belle Époque building: The 70-foot stunner sits suspended in the air like a chandelier and is ornamented with a colorful array of small and large Swarovski crystals. The sumptuous tree shines brightly against the backdrop of 10 stories of high-end luxury stores.Stroll through Prague's Old Town Square in December, and you'll be transported to a winter wonderland. Not only will you find a bustling open-air Christmas market, but there's also a nearby ice-skating rink and a Christmas Eve midnight mass. But what steals the spotlight here is the square's centerpiece, a staggering 72-foot-tall Christmas tree. This festive spruce is adorned with 36,000 lights and100 huge ornaments shaped like gingerbread men. We recommend finding a seat at one of the surrounding cafés or bars to revel in the evergreen's beauty while sipping a hot coffee or a hearty brew.In her now-famous ode to "New York," musician Alicia Keys croons that "these streets will make you feel brand new; big lights will inspire you." And that lyric seems to ring true, especially at Rockefeller Center during the holiday season. For 80 years, the Big Apple has ushered in the Christmas spirit by decorating a ceremoniously large tree. This year, you'll find an enormous 80-foot-tall Norway Spruce decked with a glittering Swarovski crystal star. And in case you're wondering, the 45,000 lights twinkling from the tree's branches are energy-efficient LEDs. But even though New York is the city that never sleeps, you'll need to visit the tree before 11:30 p.m. to see it in all its glory. (The lights turn on at 5:30 a.m. and are switched off at 11:30 p.m., until Christmas Day when they'll shine for 24 hours.)Come Christmastime, the lights from Vilnius' five-story Christmas tree set the city aglow. And yet, Lithuania's capital city is proud to note that the electricity output for all that Christmas cheer is just 2.8 kilowatts, equal to that expended by an ordinary vacuum cleaner. You'll find the tree—decorated with brightly lit snowflake ornaments—in Cathedral Square through the end of December. You'll also notice that the tree is perfectly shaped. Why? Because underneath all of those branches stands an 82-foot-tall cone frame.This might surprise you, but a Christmas tree at an outlet mall in Phoenix, Ariz. holds the title as tallest fresh-cut tree in America. To give you a reference point, this mammoth evergreen surpasses Rockefeller Plaza's iconic Christmas tree by 30 feet. This 110-foot-tall white fir tree towers over Dress Barn and Yogurberry and the many other stores in the Outlets at Anthem mall. It's garnished with 120 strings of LED lights, oversize ornaments, and a three-foot-tall copper star. And in case you're feeling sad that the Earth has lost one more gorgeous pine tree, take heart that 12 were planted in this one's stead.If you find yourself in Dortmund this December, you'll likely see the flickering lights of its enormous Christmas trees before you notice anything else about the eighth largest city in Germany. Yes, that's right: trees. The 148-foot-tall spectacle is actually the sum total of 1,700 individual red spruce trees, stuffed and stacked into a frame. Tens of thousands of lights, as well as 20 candles, create a glowing wintry scene, which you can enjoy in the Hansaplatz (market square). While admiring Dortmund's Christmas spirit, you can also partake in some holiday shopping. Hansaplatz also serves as the location of a bustling Christmas market encompassing more than 300 stalls, selling yuletide treats, and handcrafted gifts.