The Gulf of Alaska arcs at its northern edge, forming the rounded northern shore of the Pacific Ocean, a zone of great collisions. This region is where the earth's tectonic plates collide, spewing forth froths of hot lava from dozens of volcanoes, and fracturing and folding the earth with titanic earthquakes. Here, the ocean's weather hits mountains jutting miles high from the sea, growing immense prehistoric ice sheets and glaciers that carve the rock into long, deep, intricate fjords. The sea proffers prodigious biological wealth on these shores, including the salmon it unleashes into the rivers in furious swarms of life that climb over the mountains and into the Interior to spawn. Nature seems giant and superabundant along this magnificent arc of land and water. As a region, Southcentral is something of a catchall. The landforms in this part of Alaska are the most varied in the the state.  More than half of Alaska’s residents live in this region of spectacular glaciers, fjords, roadside lakes, salmon streams and ocean beaches.  From the jagged Gulf of Alaska coastline, the land rises to the Alaska Range, and Mt. McKinley, the continent's highest peak.  The Gulf Coast is generally mountainous, and is indented by massive Prince William Sound and Cook Inlet.  Inland, the land is hilly or mountainous and incised by major rivers, including the Copper, Matanuska, Susitna, Kvichak, and Mulchatna.  The Susitna River valley, sculpted by ancient glaciers, is one of the few with a broad floodplain.  Southcentral dominates Alaska, with a more highly developed transportation system than anywhere else, including a network of highways and the Alaska Railroad. Alaskans living in the Interior sometimes call portions of this part of the state "the banana belt" -- a little wry humor, and understandable when comparing winters up north with this relatively moderate climate.  The ocean influences Southcentral's weather, keeping it from being very hot or very cold while the Alaska Range of mountains forms a border at the north side of this region.  Not only does the Range block most of the cold air from the interior, but the mountain chain also retains warm ocean air here.  Coastal communities are frequently as wet as southeastern cities, but the amount of rainfall lessens considerably just a short distance inland.  Summers here tend toward cool and moist, depending on the location.   Summer temperatures range from the 50's to the 80's, with coastal temperatures being cooler than more inland locations. Geography endowed this region with several of the world's great natural places. In the east, near Cordova, the Copper River's immense, entirely unspoiled delta is the largest contiguous wetlands in the Western Hemisphere.  The Copper River Basin lies between the Chugach and Wrangell mountains and during the ice age was once the site of a large lake. Today it is a forested woodland. Cook Inlet extends north and then east from the Gulf of Alaska. It divides into two arms: Knik Arm on the north and Turnagain Arm on the south, with Anchorage on the peninsula between the two. Cook Inlet and its two arms are noted for their tidal bores - breaking waves rushing upchannel when the tide comes in. They are due to the fact that much of the inlet is too shallow to support normal flow of water when the tide comes in. With 30 to 35 feet between the high and low tides, the Inlet has the second largest range in the world after the Bay of Fundy in Nova Scotia. The reason for this enormous tidal range that is the same in Cook Inlet as in the Bay of Fundy: the length of the bay is such that the resonant frequency of the water sloshing back and forth in it is close to 12 hours, which is the frequency at which tidal forces from the moon and sun are driving it. Cook Inlet is the only place in North America where tidal bores are frequently observed. When Captain Cook explored Turnagain Arm, he observed the tidal bores, recognized the danger, and told his crew to head back out to sea. That's how Turnagain Arm got its name.  At low tide, miles of mud flats become exposed; if it were not for the occasional quicksand and possibility of tidal bores when the tide comes back in, it would be safe to walk across the entire width of the channel in some places. One would think that Turnagain Arm would be very deep because it is surrounded by mountains. However, the heavily silt-laden glacial streams drop their loads when they flow out into the calmer waters of the sea. Over the eons the silt accumulates into a mud flat which is exposed at low tide. The Matanuska-Susitna (Mat-Su) Valley consists of fertile farmland against the majestic backdrop of the Chugach Mountains.  This is Alaska’s only major agricultural area. Fertile glacial soil, long summer days, and a natural watering system as frozen ground melts, combine to produce such prize-winning vegetables as a 10 lb. carrot, a 42 lb. beet, a bunch of broccoli tipping the scales at 35 lbs., and a 105 lb. cabbage. The state's dairy industry is also in the Mat-Su Valley. The 15,000 square miles of Prince William Sound are full of glacially-carved fjords over 1,000 feet deep  and mountains that thrust out of the sea to their highest point on Mt. Marcus Baker at 13,250 feet. Waters of the Sound are protected by a series of islands which provide a protective barrier to the ocean swells. A 3,500 mile-long coastline is the boundary to the world's most northern temperate rain forest. Three million acres of forest are home to western hemlock, white spruce and Sitka spruce, some of which grow to over 100 feet tall. The communities of Whittier, Valdez and Cordova are the gateways to the waters of the Sound.  Shipping is focused at the port of Valdez, which is the southern terminus of the trans-Alaskan pipeline. Fishing, forestry, and some mining are prevalent activities in the area. On March 24, 1989, the Exxon Valdez hit a reef nearby and spilled approximately 10 million gallons of oil into Prince William Sound. Clean-up efforts ensued however, much of the region's wildlife was killed or endangered as a result of the environmental disaster. The immense Columbia Glacier is the second largest in Alaska.  It's a  440-square-mile river of ice flows into Columbia Bay in the north central portion of Prince William Sound.  This "tidewater" glacier emptied directly into the ocean. The Columbia was born in the snowfields of the Chugach Mountains and gradually meandered 23 miles beyond its ancestral fjord.  The Kenai Fjords are coastal mountain fjords whose placid seascapes reflect scenic ice bound landscapes and whose salt spray mixes with mountain mist.  Located on the southeastern Kenai Peninsula, the national park is a pristine and rugged land supporting many unaltered natural environments and ecosystems. This land boasts an icefield wilderness, crowned by the 700-square-mile Harding Icefield, one of four major ice caps in the United States. It's thought that the icefield is a remnant of the Pleistocene ice masses once covering half of Alaska. Along the coastline of the Kenai Fjords, steep valleys that were carved by glaciers in retreat.  Active glaciers still calve and crash into the sea.  Unnamed waterfalls in unnamed canyons, glaciers that sweep down narrow mountain valleys, and a coastline along which thousands of seabirds and marine mammals raise their young each year.  Sea stacks, islets, and jagged shoreline are remnants of mountains that today inch imperceptibly into the sea under the geological force of the North Pacific tectonic plate. Though the land is subsiding, a mountain platform 1 mile high still comprises the coast's backdrop. The mountains are mantled by the 300-square-mile Harding Icefield, the park's dominant feature. The icefield was not discovered until early this century when a mapping team realized that several coastal glaciers belonged to the same massive system. Today's icefield measures some 35 miles long by 20 miles wide. Only isolated mountain peaks interrupt its nearly flat, snowclad surface. These protruding nunataks - the Eskimo word meaning "lonely peaks" - rise dramatically from the frozen clutches of the Ice Age.  Here are found newly exposed, scoured, and polished bedrock and a regime of plant succession from the earliest pioneer plants to a mature forest of Sitka spruce and western hemlock. The mountains intercept moisture-laden clouds, which replenish the icefield with 35-65 feet of snow annually. Time and the weight of overlying snow transform the snow into ice. The pull of gravity and the weight of the snowy overburden make the ice flow out in all directions. It is squeezed into glaciers that creep downward like giant bulldozers, carving and gouging the landscape. Along the coast eight glaciers reach the sea, and these tidewater glaciers calve icebergs into the fjords. The thunderous boom of calving ice can sometimes be heard 20 miles away. Moose, bears, and a large population of mountain goats inhabit this region. Steller sea lions haul out on rocky islands at the entrances to the fjords. Harbor seals rest on icebergs. Killer whales, porpoises, sea otters, and several whale species also are found here. Thousands of sea birds -- horned and tufted puffins, common murres, and black-legged kittiwakes -- rear their young on steep cliffs. On the southern tip of the Kenai peninsula, Kachemak Bay is like a miniature Prince William Sound, but with people. The bay's shores are dotted with tiny towns on pilings. Humans have had a lasting impact on this environment, but the plants and wildlife continue to subsist here amidst dynamic interactions of water, ice, and a glacier-carved landscape relentlessly pulled down by the Earth’s crustal movements. The Harriman Expedition, a steamship-borne venture visiting the fjords in 1899, predicted this area's future value as a scenic tourist attraction.  He was right.   The following communities are in the south central region: Alexander Anchorage Anchor Point Big Lake Cantwell Chickaloon Chistochina Chitina Clam Gulch Cooper Landing Copper Center Cordova Crown Point Eagle River Eyak Farewell Gakona Gakona Junction Girdwood Glennallen Gulkana Halibut Cove Homer Hope Houston Iliamna Kalifornski Kasilof Kenai Knik Lazy Mountain McCarthy Meadow Lakes Mendeltna Mentasta Lake Moose Pass Newhalen Nikiski Ninilchik Nondalton Northway Junction Palmer Paxson Pedro Bay Peters Creek Pile Bay Port Alsworth Seldovia Seward Skwenta Slana Soldotna Sterling Sutton Talkeetna Tanacross Tazlina Tetlin Junction Tok Trapper Creek Tyonek Valdez Wasilla Whittier Willow