In November of 1515, Captain Antonio Tello de Guzmán, under order of Pedrarias, was sent to explore the western coasts of the Mar del Sur (South Sea discovered by Balboa). He used the overland trail between Antigua and the Gulf of San Miguel. During his exploration of the coast, he came upon a native village of fishermen. The natives called themselves and their village, Panamá, (a Cueva word meaning "Place of Abundant Fish"). The natives informed Guzmán of a trail, going north, all the way to Porto Bello, past the site of the abandoned town of Nombre de Diós. 

This trail had been used by the natives for centuries, and was well laid out. To avoid the swamps of Limon Bay, it ran a couple of leagues to the east, avoiding the lowlands and circling the headwaters of two of the tributaries of the Chagres River. They did cross the river with the help of a bridge that was constructed of vines. This bridge consisted of one thick vine to walk on, and two thinner vines were used as hand rails. There was a web of vines from each of the hand rails, connected to the thicker foot vine, helping with the prevention of your feet slipping. The crossing was at a place called Barba Coas (in the Kunah language, "Bridge Big").

Guzmán ordered Diego de Alvitez, along with a force of 80 men, to explore the route, making him the first Spaniard to cross the Río de los Lagartos, (it was named by Cristóbal Colon in 1502 and the name changed many years later to Chagre, and eventually to Chagres). The expedition took three weeks, and they returned with 10,000 pesos of gold they confiscated from the natives. Alvitez reported that the trail was much better than the one from Antigua to San Miguel. It was a little bit longer, about 18 leagues, but the mountains were much lower, and was easier and quicker to transverse the Isthmus.

When Guzmán arrived in Antigua, he reported to Pedrarias the existence of the trail. Pedrarias did nothing with the trail, since he was waiting for information from other explorers he had sent up and down the Isthmus from Panama to Guatemala searching for a better route across the Isthmus.

In 1517, Pedrarias had already made up his mind, to abandon the town of Antigua, since that was going to be taken away, as soon as the new governor arrived in Castilla del Oro. He ordered Gaspar de Espinosa, who had the distinction of being the first Spaniard to cross the Isthmus on a donkey, to build the road that Alvitez had discovered. 

He set off from Nombre de Diós, which had already been abandoned, but still contained several stone building that could be fixed up. Espinosa set up the base of his operations at Nombre de Diós, and first started the job or widening the path that went west, from Nombre de Diós to the junction of the trail between Panama and Porto Bello. This junction was equidistance from Nombre de Diós and Porto Bello. Here the trail continued south and ran alone this eastern bank of the Boqueron River until it reaches the junction of the Pequeni River. Here it continues south until it reaches the banks of the Río de los Lagartos. It crossed the Río de los Lagartos and then climbed the Cordillera, descending onto the plain that entered the town of Panamá. 

Espinosa first captured 4,000 natives from the area and used them as slave labor to build the road way. They hauled smooth river stones from the nearby rivers and streams, and laid then on the trail. These stones were covered with clay, and packed, to make a smooth surface. Along the route, the Spaniards drove the natives from their homes, and enslaved them. They used the natives huts, they encountered along the way, and used them as rest stations. When they reached the Río de Lagartos, they huge placed piles of very large boulders at intervals across the river bed. They placed trucks of large trees spanning these piles in the river. these tree trunks were shaved flat, making a road bed for the bridge. Several of these trunks were placed side-by-side, to make the bridge wide enough for carts to be transported across. At the river crossing they built store houses and an inn, and named the place, Venta de Chagre. The name of Chagre, was given to the provincial department (province) by Balboa, after a district of Spain. Although the river was named El Río de los Lagartos, the area was referred to as the district of Chagre. Eventually, people started calling the river, el Río de Chagre. This name lasted for 300 years, until somebody added the letter 's' to the name, and it became el Río Chagres.

In August of 1519, Pedrarias and his officers, made the trip from Nombre de Diós to inspect the city being built by Espinosa at Panamá. They traveled on a cobbled stone road, approximately 3 feet wide all the way to Panamá and reached Panamá by August 15th. 

Since Nombre de Diós, lacked a good defensible harbor, a road was built to connect Nombre de Diós to Puerto Bello was built sometime in the 1590's. This road was called El Camino Real, was about 50 miles long, and was wide enough, to allow two carts to cross one-an-other traveling in opposite directions, and without driving on the embankment. The Spanish spared no expense in the construction of this road.

Because of the many problems with this road, Spain ordered a survey of the region, to see if there was a better route. In 1533, Licentiate Espinosa recommended that a new road be built. He advised the King, that a much better route would be, connecting Panamá to the town of Cruces, on the banks of the Chagres River. This was about 20 miles from Panamá. Once on the Chagres River, boats could be used to navigate to the Caribbean. El Camino a Cruces, the Las Cruces Trail, is the road built to connect the city of Panamá to the town of Cruces. From Cruces,  passage was continued  by Cayucos and small boats, down the Chagres River to the mouth of the Chagres, on the Caribbean Sea. At the mouth of the Chagres, the small town of Chagres, was fortified. El Castillo de San Lorenzo was built on a bluff, overlooking the area. From Chagres, treasures and goods were transported to the Kings Warehouse in Porto Bello, to be stored until the Treasure Fleet left for Spain. Most of the gold and silver, was stored in Panamá, until word was received that the Treasure Fleet, was leaving Cartagena to Porto Bello. Overland, the gold and silver was transported on the back of mules, sure footed animals were needed for the rough trip. Long mule trains were handled by Negro slaves across the Isthmus.

In 1521, a Spaniard wrote the King describing his trip across the Isthmus from Nombre de Diós to Panamá. He related that the first part of the journey was the most difficult because of the many rivers that needed to crossed, the mountains that had to climb, and the thick forest that had to be penetrated. He estimated that the route was about 20 leagues in length (1 league is approximately 3 miles). He said that it was about 8 leagues from Nombre de Diós to the land of the Indian Cacique, Juanaga, on the banks of the Capira River, and this took one long day of travel. This was the worst part of the trip. On the second day, he traveled another 8 leagues going up to the continental divide, to the Chagres River. It was another 2 leagues to the place the river was forded, a place called Puente Admirable. This was a natural bridge crossing the river. From there, the road was pleasant and 2 leagues to Panamá. This part of the trip was down hill and crossing some pastures, where the residents of Panamá maintained herds of cattle. It should be noted that he traveled across the Isthmus during the dry season. During the rainy season, the trip took much longer and was much more arduous. In this letter, he mentions to the King, that a much better route across the Isthmus would be navigating up the Chagres, instead of the terrible overland route from Nombre de Diós.

After leaving the town of Cruces, there was a series of rapids that had to be negotiated. Because of them and low water levels of the Chagres River during the Dry Season, the town of Gorgona, was sometimes used. This town was to the west of Cruces, and it made navigating down the Chagres, much easier. The Gorgona Trail, followed the Cruces Trail, for a while, and then took off on it own, near the present day community of Cardena, in the Canal Zone. In 1736, Nicolas Rodrigues recommended that the road to Gorgona be improved and paved, and abandon the road to Cruces. This recommendation was never followed, and very little of this trail exists today.

The trip from Panamá to San Lorenzo and then Porto Bello, was easier then the return trip. This was OK, since the purpose of this route was to insure that the heavy treasures reached the Caribbean safely. The trip back, was much more difficult. It required taking dugouts, (Cayucos or Piraguas) and small boats, and rowing up the Chagres River, against the current.  

This road served the Spanish well for more than three centuries. Many treasure trains passed through it as they moved the treasures from Peru and the Pacific to the Atlantic and then on to Spain. Merchandise from Spain, and her colonies was transported to Panamá, which was the center for trade, for Central and South America.

Once they finally arrived in Panamá City, they then would have to wait for a ship to arrive in Panamá, that would take them to California. Some times, travelers were stranded in Panamá City, for weeks and months. Out side the city walls, a tent city was erected by all of the travelers that could not afford the cost of the expensive hotels. Some travelers went as far as Chorrera, to live while the waited for a ship to take them to California.  All this time, paying for expensive hotel rooms and food.  Some unfortunate travelers was abused all the way starting and ending with unscrupulous ship captain, to highway men on the trail 

Some of these problem did not go away, until the construction of the Panamá Railroad. When it was completed in 1855, the trip across the Isthmus was reduced to 1 hour. The diseases and pestilence did not go away, until the discovery of the relationship between Malaria and Yellow Fever, and the mosquitoes in Cuba by Dr Carlos Finlay of Havana in 1881. When the United States, took over the construction of the Panamá Canal, Colonel George Gorgas, an army doctor, that was in Cuba, when the Dr. Finlay demonstrated the connection of the mosquitoes and yellow fever. Gorgas was given the task of cleaning up Panamá, and he was successful, making Panamá, one of the healthy places in the world.

This is a map from 1750 showing El Camino Real between Porto Bello and Panamá and El Camino a Cruces.

Click on the map, to see a larger image.