位于亚利桑那州的大峡谷国家公园中的大峡谷深1500米，分割了科罗拉多河，是世界上最壮观的峡谷。它的地质构造可以追溯到20亿年前，同时它也保留了大量的人类适应当时恶劣环境的遗迹。
大峡谷位于美国西部亚，利桑那州西北部的科罗拉多高原上。是地球上最伟大的地理奇迹之一，它的宽度惊人，向人们揭示了弥足珍贵的地球历史资料。6500万前地球漂移的过程中有一块巨大的陆地被抬升到高于海平面1．5公里，形成了今天的科罗拉多高原。距今600~1000万年里，科罗拉多河逐渐侵蚀掉层层岩石；与风、雨、雪、冷、热等因素的腐蚀作用相结合，形成了一条天堑，深1英里，宽18英里。大峡谷地层多样，显示了地球自2亿年前的变更历史。地层里的化石，可追溯到50000万年前。现在科罗拉多河仍在侵蚀着大峡谷。
大峡谷大体呈东西走向，东起科罗拉多河汇入处，西到内华达州界附近的格兰德瓦什崖附近。形状极不规则，蜿蜒曲折，迂回盘旋，峡谷顶宽在6~30公里之间，往下收缩成V字形。两岸北高南低，最大谷深1500多米，谷底水面宽度不足千米，最窄处仅120米。峡谷的壮观景色举世无双。由于河谷地层在结构、硬度上的差异，千百年河水的冲刷，在长长的峡谷间，鬼斧神工般雕琢出许许多多千姿百态的奇峰异石、峭壁石柱。谷壁地层断面，节理清晰，层层叠叠，就像万卷诗书构成的图案，缘山起伏，循谷延伸。 从谷底向上，沿崖壁出露着从前寒武纪到新生代的各个时期的岩系，水平层次清楚，并含有代表性生物化石，被称为“活的地址史教科书”。由于峡谷两壁的岩石性质、所含矿物质不同，在阳光照射下像一块五彩斑斓的调色板。
大峡谷分南、北两岸，中间有水相隔，气候差异很大。南岸的大部分地区海拔1800~2000米，而北岸比南岸高400~600米。南岸年平均降水量仅为382毫米，北岸则高达685毫米左右。
The Grand Canyon National Park is one of the oldest United States National Parks. Within the park lies the Grand Canyon， a gorge of the Colorado River， considered to be one of the major natural wonders of the world. The park covers 1，902 mi2 (4927 km2).
The area around the Grand Canyon became a United States National Monument on January 11， 1908 and was designated National Park on February 26， 1919. The creation of the park was an early success of the environmental conservation movementconservation movement 自然保护运动； its National Park status may have helped thwart proposals to dam the Colorado River within its boundaries. (Lack of this fame may have enabled Glen Canyon Dam to be built upriver， flooding Glen Canyon and creating Lake Powell).
The Grand Canyon itself - really an extensive system of tributarytributary adj.进贡的， 附庸的， 从属的， 辅助的， 支流的 n.进贡国， 附庸国， 支流 canyons - is neither the largest or deepest canyon in the world， but is valued for the combination of large size， depth， and the exposed layering of colorful rocks dating back to Precambrian times. It was created by erosion from the Colorado River and its tributaries.
One of the world，s vast and beautiful wonders， the Grand Canyon is a mustsee when visiting Arizona. The walls descend more than a mile to the canyon floor and run 277 miles from end to end. Visitors flock to Grand Canyon National Park， making it one of the country，s top 10 mostvisited national parks.
Access to the park is available from entrances on the South Rim， the North Rim and the eastern edge. The canyon，s western edge is accessible via roads on the Hualapai Indian Reservation， which is covered later in the Kingman， Lake Mead and Grand Canyon West section.
Because of its proximity to Flagstaff and Williams， most visitors travel to the canyon，s South Rim， which is open yearround. Here， Grand Canyon Village offers visitors six lodging choices， several restaurants， gift shops and a general store. The Canyon View Information Plaza， a visitor center located at Mather Point， has brochures， maps and other information about the park， as well as a nonprofit bookstore and gift shop.
Grand Canyon Village has a number of parking areas， but in the peak season of summer， the park experiences crowding and automobiles compete for spaces. Rangers advise visitors to park their cars and ride the free shuttle busesshuttle bus n.豪华轿车. Three routes include the Village Loop， the Hermit Road Loop and the Kaibab Trail Loop. These shuttles provide an overview of the canyon and easy access to its many scenic overlooks. The buses operate daily， dropping off and picking up passengers along the routes. At designateddesignated 指定的， 派定的 areas in the park， rangers educate visitors about the canyon，s geology and natural environment with lectures and guided walks scheduled throughout the day.
Xanterra Parks & Resorts operates eight hotels and lodges within the park - six on the South Rim， one on the North Rim， and Phantom Ranch， the only noncamping lodging at the bottom of the canyon. Additional lodging is available six miles south of the park in Tusayan， 30 minutes south in Valle， an hour south in Williams， one hour east in Cameron and 90 minutes away in Flagstaff. These cities can be used as a base for exploring the canyon. The nearest gas station to the park is in Tusayan.
Visitors who want to explore the canyon “in depth” can descend below the rim. To ensure an authentic natural encounter， and to preserve the canyon，s unique ecology， developed facilities below the rim are limited. Besides camping， Phantom Ranch provides the only lodging， and reservations must be made well in advance. Due to cancellations， however， it is sometimes possible to call for sameday reservations. Located on the north side of the Colorado River， Phantom Ranch has individual and dormitorystyle cabins. Meals are served boardinghouse style， and showers are available. Bright Angel Campground offers primitiveprimitive adj.原始的， 远古的， 粗糙的， 简单的 camping facilities at the bottom of the canyon.
Hiking， backpacking and river rafting are among the adventures that await those who want a close encounter with the canyon，s rugged expanse. Visitors can dayhike into the canyon， but overnight stays require permits from the park，s backcountry office or reservations at Phantom Ranch. Hikers have several options to reach the bottom， including the 9.3mile Bright Angel Trail or the 7.3mile South Kaibab Trail. Though both trails are strenuousstrenuous adj.奋发的， 使劲的， 紧张的， 热烈的， 艰辛发奋的， the South Kaibab Trail is steeper. The canyon is beautiful， but its weather can be unforgiving. The heat of summer can pose serious threats to hikers who are not prepared. Consult with park rangers before your trip.
The canyon，s famous， surefooted mules offer a lessstrenuous journey. A narrated 12mile round trip to Plateau Point ends at a promontory 1，000 feet directly above the Colorado River. Or， enjoy a mule ride to Phantom Ranch， returning the next day. Reservations for rooms， Phantom Ranch and mule trips can be made up to 13 months in advance.
