Royal Tunbridge Wells (formerly, until 1909, and still commonly Tunbridge Wells) is a town in Kent, England, 30 miles (50 kilometres) southeast of Central London. It lies close to the border with East Sussex on the northern edge of the High Weald, whose sandstone geology is exemplified by the rock formation High Rocks. The town was a spa in the Restoration and a fashionable resort in the mid-1700s under Beau Nash when the Pantiles, and its chalybeate spring, attracted visitors who wished to take the waters. Though its popularity as a spa town waned with the advent of sea bathing, the town still derives much of its income from tourism. The prefix "Royal" was granted to it in 1909 by King Edward VII; it is one of only three towns in England with the title.

The town had a population of 59,947 in 2016, and is the administrative centre of Tunbridge Wells Borough and in the parliamentary constituency of Tunbridge Wells.

Evidence suggests that Iron Age people farmed the fields and mined the iron-rich rocks in the Tunbridge Wells area, and excavations in 1940 and 1957–61 by James Money at High Rocks uncovered the remains of a defensive hillfort. It is thought that the site was occupied into the era of Roman Britain, and the area continued to be part of the Wealden iron industry until its demise in the late eighteenth century. An iron forge remains in the grounds of Bayham Abbey, in use until 1575 and documented until 1714.

The area which is now Tunbridge Wells was part of the parish of Speldhurst for hundreds of years.^{[clarification needed]}

The origin of the town today came in the seventeenth century. In 1606 Dudley North, 3rd Baron North, a courtier to King James VI and I who was staying at a hunting lodge in Eridge in the hope that the country air might improve his ailing constitution, discovered a chalybeate spring. He drank from the spring and, when his health improved, he became convinced that it had healing properties. He persuaded his rich friends in London to try it, and by the time Queen Henrietta Maria, wife of King Charles I, visited in 1630 it had established itself as a spa retreat. By 1636 it had become so popular that two houses were built next to the spring to cater for the visitors, one for the ladies and one for the gentlemen, and in 1664 Lord Muskerry, Lord of the Manor, enclosed it with a triangular stone wall, and built a hall "to shelter the dippers in wet weather."

Until 1676 little permanent building took place—visitors were obliged either to camp on the downs or to find lodgings at Southborough—, but at this time houses and shops were erected on the walks, and every "convenient situation near the springs" was built upon. Also in 1676 a subscription for a "chapel of ease" was opened, and in 1684 the Church of King Charles the Martyr was duly built and the town began to develop around it. In 1787 the antiquarian Edward Hasted described the new town as consisting of four small districts, "named after the hills on which they stand, Mount Ephraim, Mount Pleasant and Mount Sion; the other is called the Wells..."

In the 1680s there was a building-boom in the town: carefully planned shops were built beside the 175-yard-long (160-metre) Pantiles promenade (then known as the Walks), and the Mount Sion road, on which lodging house keepers were to build, was laid out in small plots. Tradesmen in the town dealt in the luxury goods demanded by their patrons, which would certainly have included Tunbridge ware, a kind of decoratively inlaid woodwork.

"They have made the wells very commodious by the many good building all about it and two or three miles [three or five kilometres] around which are lodgings for the company that drink the waters. All the people buy their own provisions at the market, which is just by the wells and is furnished with great plenty of all sorts of fish and fowl. The walk which is between high trees on the market side which are shops full of all sorts of toys, silver, china, milliners and all sorts of curious wooden ware besides which there are two large coffee houses for tea, chocolate etc. and two rooms for the lottery and hazard board (i.e. for gambling)."—Celia Fiennes, 1697