The Arches NP is one of the most rewarding National Parks to visit in the Southwest of the USA. Unfortunately1 it takes approximately one day by car to get there from the Grand Canyon NP, so many round trips will leave it out, taking the Natural Bridges Monument as a substitute. But if you have seen some of the NPs in that area, you will get 'homesick' rather for the Arches NP than for the Grand Canyon2. The Delicate Arch, which can be seen to the right, has even become the un-official state symbol of Utah.
Arches has been established as a National Monument in 1929 by President Herbert Hoover and was 'promoted' to be a National Park in 1971.
How to get there
Moab, Utah, situated on Highway 191, is the closest town. The entrance to the NP is app. 5 miles (8 km) north of Moab. The nearest airports, served by commercial airlines, are Grand Junction, CO, and Salt Lake City, UT. A Greyhound route travels along Interstate 70, with stops at Grand Junction, CO, and Green River, UT. Unfortunately, there is little public transportation to and from Moab. There are some commercial van services between Salt Lake City (resp. Grand Junction) and Moab, but as there is no public transportation from Moab to the NP you'll have to rent some sort of vehicle anyhow.
The Arches NP is basically a desert park, which means that the climate is extremely dry, but not necessarily hot throughout the year. At summer day temperatures will regularily exceed 100°F (38°C), whereas at winter they will drop even below 32°F (0°C). A day/night temperature range of more than 50°F (28°C) is not unheard of.
Today the Arches NP covers an area of 76,519 acres (310 km²). Scattered over that area the visitor finds more than 2,000 cataloged arches of all sizes, ranging from tiny 3-ft3 arches up to the 306 ft(100 m) of the Landscape Arch, which is the longest natural sandstone arch in the world.
The arches may have provided the name for the National Park, but many other formations are found there: Pinnacles, spires, fins, balancing rocks, ..., are forming a dramatic scenery against the backdrop of the La Sal Mountains4.
300 million years ago, the area that is now known as the Colorado Plateau was covered by oceans that finally evaporated, leaving a gigantic salt bed behind them. This saltbed, up to thousands of feet thick was covered with sand and debris that was carried here by floods and winds. Most of that sand was compressed into solid stone (Sandstone) over the millions of years. The weight of these layers of stone caused an immense pressure onto the saltbed blow. Salt under high pressure is not stable, and the salt layer started to shift, it buckled and pushed some of the lighter rock layers into domes. In other areas the rock layers were wrinkled like old thick leather that is exposed to the sun. As soon as the surface of the area was no longer intact, the natural erosion of sun, wind, water and frost started its sculpturing work. It is still active today.
Lifespan of an Arch
When the saltbed pushes the rock upwards, the wrinkles and vaults sometimes form huge fins that are cleared of loose material by wind and water. Most of these fins are degraded by the erosion, but some of them, with the right hardness and balance of the material, will withstand for quite a while. Erosion, anyhow, has some very hard teeth. it continues to gnaw at these fins, and sometimes it bites little holes through them. This is the birth of an arch. As time goes by, those holes will be enlarged by the erosion, and finally only a thin ribbon of rock may be the last reminder of a former fin (as is the case with Landscape Arch).
Arches vs Natural Bridges
Does it make a difference at all? Yes, it does (at least for the geologists). An arch starts with a little hole that grows upwards, i.e. the erosion bites off pieces from the top side of the hole. A natural bridge, on the other hand, is created by flowing water that digs deeper and deeper.
Ecology (standard disclaimer for a desert park)
As in any hot and dry environment, life is slow here. Very slow. Sometimes it seems as if the dry heat had won its fight against the deplorable plants, but once the rain comes5 the desert explodes with blossoms. If you are lucky enough to go there when this happens, you'll get to see something that you'll never forget. But most of the time, vegetation has to reduce its metabolism dramatically. This makes it extremely vulnerable to intrusion. One single step beside the path may cause a setback of decades for the vegetation and especially for the cryptobiotic6 crust at the very bottom of the life chain. So the standard rule that says "Take nothing but pictures, leave nothing but footprints" should be "Do not even leave footprints" in this particular case.
Camping in the Park
Devil's Garden campsite is open all year and operated on a first-come-first-serve basis. At the time of the writing of this Entry (late 2001) the fee is $10 per night. From March to October visitors have to pre-register at the entrance station. As there are only 52 sites, the campsite may be fully occupied even before 9:00 am. Fees and rules may be subject to change, you'd better check that at the Arches page of the National Park Service, where most of the factual research for this article was made.