Old Town Hoi An, the city's historic district, is recognized as an exceptionally well-preserved example of a Southeast Asian trading port dating from the 15th to the 19th century, its buildings and street plan reflecting a unique blend of influences, indigenous and foreign. Prominent in the city's old town, is its covered "Japanese Bridge," dating to the 16th-17th century.

Between the seventh and 10th centuries, the Cham (people of Champa) controlled the strategic spice trade and with this came tremendous wealth. The former harbor town of the Cham at the estuary of the Thu Bồn River was an important Vietnamese trading centre in the 16th and 17th centuries, where Chinese from various provinces as well as Portuguese, Japanese, Dutch and Indians settled. During this period of the China trade, the town was called Hai Pho (Seaside Town) in Vietnamese.

Originally, Hai Pho was a divided town with the Japanese settlement across the "Japanese Bridge" (16th-17th century). The bridge (Chùa cầu) is a unique covered structure built by the Japanese, the only known covered bridge with a Buddhist temple attached to one side.

The early history of Hội An is that of the Cham. These Austronesian-speaking Malayo-Polynesian peoples created the Champa Empire which occupied much of what is now central and lower Vietnam, from Huế to beyond Nha Trang.Various linguistic connections between Cham and the related Jarai language and the Austronesian languages of Indonesia (particularly Acehnese), Malaysia, and Hainan has been documented. In the early years, Mỹ Sơn was the spiritual capital, Trà Kiệu was the political capital and Hội An was the commercial capital of the Champa Empire - later, by the 14th century, the Cham moved further down towards Nha Trang. The river system was used for the transport of goods between the highlands, inland countries of Laos and Thailand and the low lands.

In 1535 Portuguese explorer and sea captain António de Faria, coming from Da Nang, tried to establish a major trading centre at the port village of Faifo. Hội An was founded as a trading port by the Nguyễn Lord Nguyễn Hoàng sometime around 1595. The Nguyễn lords were far more interested in commercial activity than the Trịnh lords who ruled the north. As a result, Hội An flourished as a trading port and became the most important trade port on the East Vietnam Sea. Captain William Adams, the English sailor and confidant of Tokugawa Ieyasu, is known to have made one trading mission to Hội An in 1617 on a Red Seal Ship. The early Portuguese Jesuits also had one of their two residences at Hội An.

In the 18th century, Hội An was considered by Chinese and Japanese merchants to be the best destination for trading in all of Southeast Asia, even Asia. The city also rose to prominence as a powerful and exclusive trade conduit between Europe, China, India, and Japan, especially for the ceramic industry. Shipwreck discoveries have shown that Vietnamese and Asian ceramics were transported from Hội An to as far as Sinai, Egypt.

Hội An's importance waned sharply at the end of the 18th century because of the collapse of Nguyễn rule (thanks to the Tây Sơn Rebellion - which was opposed to foreign trade). Then, with the triumph of Emperor Gia Long, he repaid the French for their aid by giving them exclusive trade rights to the nearby port town of Đà Nẵng. Đà Nẵng became the new centre of trade (and later French influence) in central Vietnam while Hội An was a forgotten backwater. Local historians also say that Hội An lost its status as a desirable trade port due to silting up of the river mouth. The result was that Hội An remained almost untouched by the changes to Vietnam over the next 200 years.

About 18 km from the mainland is the cluster, Cham Island. With an area of 1,549 km2 (25% accounting for total natural area). It is within the coordinates latitude 15o52'30 '' to 16o 00'00 '' North and longitude108o24'30 '' to 108o34'30 'East. The cluster Cham Island contains many small and large islands, including Hon Lao, Hon Mo, Hon Dai, Hon Ong, Hon Tai, Hon La, Hon Kho ( Kho Me, Kho Con), and Hon Nom. Cham Island has been recognized as a world biosphere reserve on May 26, 2009.

Hoi An is also located near the Chu Lai airport in Quang Nam province, and Da Nang modern international airport. Hoi An has a special advantage, as it lies in “ the central cultural heritage road”, which includes: My Son – Hoi An – Hue. This is considered a favourable travel route, and attracts a large number of tourists to Hoi An, from home and abroad

Calm mild weather is now limited to the season of May/June - end of August when the seas are calm and wind changes direction and comes from the South. The remainder of the year the weather is intermittent between rain & cold and hot & mild. Popular activities such as visiting offshore Cù lao Chàm islands are only guaranteed to be likely during the short season of end of May to end of August, which is the high season for domestic tourism.

Today, the town is a tourist attraction because of its history, traditional architecture and crafts such as textiles and ceramics. Many bars, hotels, and resorts have been constructed both in Hội An and the surrounding area. The port mouth and boats are still used for both fishing and tourism.