Living in a sliver of a country hemmed in by two oceans, in a land where the rivers are as wide as lakes and the lakes are so big the Spanish conquerors called them freshwater seas, most Nicaraguans consider themselves sailors by heritage.

Boats are part of their national character--and the main form of transportation for the more than 500,000 Nicaraguans who live on islands or along river banks without roads.

"We have ocean on the outside and, inside, rivers and lakes," said Ariel Montoya, editor of the literary magazine Decenio. "That has made us adventurers."

It's a tradition that had been in danger of vanishing as remote communities pressured the government for roads. But after watching the destruction that occurs when a highway is cut through the wilderness, giving access to loggers and their buzz saws, authorities here are promoting boat travel and transportation as the best hope for preserving the country's forests and jungles.

As a result, Nicaragua's 842 miles of navigable waterways--most in the eastern part of the country, which has a single, partially paved highway--are receiving new recognition as an alternative to roadways.

It's a revival of sorts. Until the Panama Canal opened in 1914, Nicaragua was the closest thing available to the maritime passageway to the Far East that Christopher Columbus had sought, although he never realized it.

The famous explorer left Nicaragua disappointed nearly 500 years ago after running aground at El Bluff near the mouth of the Escondido River, which runs through--and brings life to--this remote community. He then sailed past the San Carlos River farther south, which became the 19th-century shortcut between the Atlantic and Pacific oceans.

During the California gold rush, Cornelius Vanderbilt's boats took '49ers who came by ship from New York up the San Carlos to Lake Nicaragua. After crossing the lake on the steamer Victoria, only 12 miles of land divided them from the Pacific Ocean and another Vanderbilt steamer to California. That cut thousands of miles off a journey around Cape Horn.

Beyond the historical significance of the waterways, boats are the cheapest form of transportation in remote areas without roads. A plane ticket from Bluefields, at the mouth of the Escondido River, to Corn Island in the Caribbean costs $22. The boat fare is $3. In addition, not even commuter lines fly into communities such as El Rama.

So most Nicaraguans take the boat, hanging hammocks from the rafters or staking out a temporary territory on a bench. From their makeshift berths, they watch for spider monkeys, parrots and the river's colorful human inhabitants.

Recently, a boat with the unfortunate name of Titanic made its way down the San Juan River, which divides Nicaragua from Costa Rica. A canoe approached rapidly from the shore, and, fearing a collision, passengers gestured wildly to the rower.

At the last minute, 63-year-old Maria Hernandez neatly pulled her canoe alongside the Titanic. She threw ropes that the relieved passengers tied to the boat to hold her canoe steady. Then she began selling box lunches wrapped in banana leaves.

Hernandez then swung herself onto the boat, carrying a bucket of tamales, which she emptied on one walk around the deck. In less time than a coffee break, she was back in her canoe, rowing for shore.

Lucky travelers catch a boat, such as the Titanic, that is designed to carry passengers. But those in too much of a hurry to wait for the sporadic passenger boats must ride on a freighter, such as El Isleno, which leaves El Rama every Sunday for Corn Island with a stop at El Bluff.

These passengers must find a place to stand or squat for 12 hours or longer among the charcoal, bottled water, natural gas and vegetables en route to Nicaragua's only Caribbean island.

"The hardest part is navigating at night," said Capt. Mateo Vidaure, 28, who has been a sailor for five years. "Then, when there is bad weather and the sea is rough, it is difficult."

Nicaragua's boatmen are an independent lot, most of them owning only one or two of the country's 112 registered commercial boats and "pangas," which resemble canoes with outboard motors.

"There are only three real companies, and none of them has more than five boats each," said Miguel Malespin, Nicaragua's director of ports and navigational development. "None is big enough to dominate the market."

Beyond their mundane function as highways for commerce and travel, Nicaragua's lakes and rivers also are its playgrounds. The national favorite is Lake Cocibolca, better known as Lake Nicaragua. On Sunday afternoons, adults sip rum and savor fish at lakeside restaurants while children splash in the shallow water near the shore.

A Nicaraguan's idea of privacy is a cottage on one of the lake's "isletas," an archipelago of hundreds of islands, most no bigger than a back yard, some merely a few minutes' boat ride from Granada. The only electricity comes from generators.

Interspersed among the vacation homes of the wealthy and the aspiring are tiny islands with fishermen's shanties. Ferrying weekend visitors out to the islands of their hosts is an extra source of income for the fishermen.

CAPTION: A riverboat carries passengers and cargo on the San Juan River in Nicaragua, which has centuries of maritime history and 842 miles of waterways that are making a comeback as alternatives to roads.