A seaside town is often called a resort. It is a place by the sea whose main task is to look after holidaymakers. That is different to a port, which is a town that looks after cargo and passengers in ships.

The idea of a seaside town is quite new compared to ports. It all came about until about 50 years before Victorian times. Towards the end of the 18th century doctors in England began to tell the very wealthy that drinking sea water and taking sea air was good for them. But, perhaps even more important, seaside resorts became popular with the upper classes because the seaside took the fancy of princes, kings and queens. So some wealthy people started to build large houses by the sea for themselves, while others built grand hotels for visitors. These were very exclusive and meant only for the super-rich, and as a result, the first seaside towns often remained small places.

During The 19th century more people became wealthy and gradually even workers were given (unpaid) holiday time each year. The first railway line was built in 1825, and between 1840 and 1880 railways reached all over the country. The railway owners were keen to get as many people using their trains as possible, so they gave cheap fares at some times and encouraged towns at the end of their railway lines to grow to take holidaymakers. Many railway companies also owned land on the coast.

It was a British idea in particular because the UK has so much coast so close to its major cities. In countries like the USA most people live a long way from the coast, so seaside holidays have never been as popular. However, along the east and west coasts, and near to big cities such as Los Angeles, San Francisco and new York, seaside resorts did spring up (Santa Monica, next to Los Angeles, Coney Island next to New York and, a little to the south, Ocean City and Atlantic City.

The very wealthy kept some towns out of reach of the lower classes. By contrast, places that were close to big cities mostly catered for day trippers or the less well off.

The towns catering for the lower classes knew they had to entertain the visitors (or they might break the place up). Building entertainments, such as music halls and amusement arcades, were a good way of getting more money from the visitors, too.

Some parts of the country did not have wide beaches, or were too out of the way, or the landscape too hilly for big seaside towns to develop. The very biggest seaside resorts were close to large cities in places where there were wide beaches and lots of room to build.

With the start of air travel in the 20th century, people started to go elsewhere for their holidays and so many older seaside towns have had a difficult time.