In the Azores you will find the only tea plantations in Europe, which produce excellent teas, processing the leaves on vintage 19th  century English machinery.  

Ribeira Grande, in São Miguel  Island, is home to the two tea factories and a plantation--the only such  plantation in Europe, courtesy of the island's balmy  climate. (It rarely  gets below 50°F or above 80°F in the Azores.) Walk the  fields, tour the  factories and have a cup of tea in a stone-walled tea room.

Chá Porto Formoso (+351 296 442 342; http://www.chaportoformoso.com/)  is on the main road between Ribeira Grande and São Brás. It opens 10am-5pm,  Monday to Saturday, and entrance is free.

Chá Gorreana (+351  296 442 349; http://www.gorreana.com/  ), is 1.5km along the same road just beyond the turning for São Brás. It opens  9am-6pm daily; entrance is free. Gorreana, the older of the two and by far the  bigger  operation, has been growing tea since 1883, and is one of the  original  19th-century Azorean tea producers. According to the time of  year, it is possible to have a look at all the different stages of tea  production, from picking - a mechanical procedure which takes place during the  drier months between April and September - to packing, which is done by a  group of local women sitting at tables, shoveling piles of tea leaves into  packets. In  between are several vital stages: wilting; an hour-long  rolling process which starts to crush the leaf; three hours' fermentation; and  a 20-minute drying period at a temperature of 100s? this creates black tea;  green tea is produced  from the same leaves, but they are steamed early  on in the process to stop fermentation. The seeds from which the original  Azorean tea bushes grew are  thought to have been brought to São Miguel  by a commander of the Portuguese Royal Guards, returning home after a tour of  duty in the Brazilian city of Rio de Janeiro in the early 19th century. At  first, the bushes were grown for their ornamental value; it wasn't until a  virus threatened to decimate the orange-growing industry on the islands more  than half a century later that experts were brought over from China to  introduce the Azoreans to the fine art of tea production. São Miguel, with its  rich volcanic soil and temperate climate proved a fertile environment for the  bushes. Plantations were established, and 14 factories opened up around the  island before the turn of the century.

The Gorreana factory (and the  smaller Porto Formoso, about 1.5km away) both produce three varieties of black  tea. A single bush can produce leaves for all three. Tea varieties are determined according to where on the bush the leaves are picked from: orange  pekoe, the most delicately flavored of the three, comes from the bud and first  shoot; pekoe, a less-flavored variety, is from the second leaf; and Broken  Leaf, the least aromatic of the three, is made from fragments of the remaining  leaves.

 The factory experience at Gorreana ends up in what  appears to be the works canteen, a small area where visitors and workers can  help themselves to a cup of tea, before getting back to work or setting off to  explore more of the island.

Porto Formoso is a nice place to  savor the drink. The factory produced tea from the 1920s until the 1980s;  then, eight years ago, it reopened. A limited amount of tea is made from the  bushes grown on the three hectares around the property; there are plans to  double the size of the plantation.