The spa cup: why it looks the way it does, and the wisdom hidden in that shape

An object nobody notices — and yet it is ingenious

You arrive in Mariánské Lázně, buy a spa cup, fill it at the Cross Spring and set off along the colonnade. It feels like folklore: that slightly odd flat little mug with a handle you drink from.

In reality you are holding an object that evolved over four centuries as a medical aid. Every one of its peculiarities — the flat shape, the hollow spout, the marks along the side — came about as an answer to a specific practical problem. Nothing about it is accidental.

At first it was about not burning yourself

The spa cup tradition goes back to the 16th century and originated in the Karlovy Vary region. The Karlovy Vary springs are hot — and so the first "cups" were simply glasses in a holder, so that patients would not burn their fingers while drinking the scalding water.

Materials then changed according to what was available and affordable:

• 17th century — stoneware vessels, ordinary mugs and bulbous onion-shaped pots
• milk glass — a cheap imitation of expensive porcelain
• early 19th century — the rise of porcelain

In Mariánské Lázně, however, that history has a chapter of its own. Porcelain was very expensive at the time, so from the early 19th century glass cups spread here on a mass scale — and glass remained dominant in Mariánské Lázně until the mid-20th century. The local town museum keeps a fine collection, including crystal cups from the Moser glassworks and a commemorative piece marking the 1904 meeting of Emperor Franz Joseph I with the British King Edward VII.

How the shape gradually flattened

Look at cups in a museum display arranged by age and you will see a clear line of development:

mug → egg-shaped or conical form with a handle → flat shape that loses the handle

Why flat, specifically? Because the spa guest walks with the cup. They are not sitting at a table. A flat cup rests comfortably in the palm, does not get in the way while walking, slips into a coat pocket or handbag and does not chafe. The shape adapted to how the object is actually used — exactly as any industrial designer would describe it today.

The hollow spout: the cleverest detail of the whole cup

The most characteristic feature — the hollow handle that doubles as a spout — appears only at the end of the 19th century. It is not decoration and not an accident. It solves several problems at once:

1. You drink while walking

The basic rule of the drinking cure is: the patient should walk while drinking the mineral water. The water is sipped slowly, in small mouthfuls, in motion. But drinking from an open mug while walking along a crowded colonnade is a reliable recipe for a soaked coat — your own and other people's. The spout solves this elegantly: you sip, you do not spill.

2. It protects the teeth

Mineral water is loaded with minerals and tends to be more acidic. When sipped through a straw, it does not come into direct contact with tooth enamel. This logic, which dentists today recommend for acidic drinks in general, was handled by our ancestors a hundred and thirty years ago — through the shape of the vessel.

3. You do not get burned

The original Karlovy Vary problem applies here too: you hold hot water by the spout and drink it in a thin stream instead of putting your lips to a scalding rim.

4. It forces you to drink slowly

And this is perhaps the loveliest part. The narrow spout physically makes it impossible to down the cup in three gulps. The drinking cure, however, rests precisely on slow, spread-out intake — the water should pass through the body gradually, not in bursts. So our ancestors did not enforce the correct pace by lecturing. They built it into the vessel. The cup drinks slowly for you, whether you like it or not.

The marks along the side: dosage, not decoration

On older cups you will find marks or measuring lines. These are not decorative stripes — they are a dosing gauge.

The spa physician did not simply prescribe "drink mineral water". He prescribed a specific spring, a specific quantity and a specific time. A cup with marks was effectively a wearable prescription: the guest knew where to fill it and how far not to fill it. Even today, a drinking cure should be discussed with a doctor — the springs differ in composition, and more does not mean better.

When the tool also became a souvenir

Once you carry an object in your hand all day, you start wanting something beautiful on it. The decoration of the cups therefore went through its own evolution:

• at first just a plain inscription with the name of the spa
• then painted scenes of places, allegories of health, flowers and birds
• later relief, three-dimensional motifs, once porcelain production allowed it
• and in Mariánské Lázně additionally cut crystal, coloured glass and engraving

Personalisation was popular too — a guest could have initials or a full name engraved. The cup was thus simultaneously a health aid, a memento of the stay and, to a degree, a calling card.

The wisdom in it

Put it all together and something remarkable emerges. The spa cup is functional design long before anyone called it that:

It is not a souvenir you happen to drink from. It is a medical device that happened to become a souvenir.

How to use it today

You can buy a cup on the colonnade and in shops all over town — from simple porcelain to cut glass. And then all that remains is to observe what people built into its shape a hundred and fifty years ago:

1. Fill it at the prescribed spring — the springs overview will tell you which is which
2. Drink slowly, in small sips — the spout will help you
3. Walk while you do it — ideally along the Main Colonnade, best of all during a promenade concert by our orchestra
4. Follow your doctor's advice — with the drinking cure the dose really matters

Next time you take a sip, notice the shape in your hand. It is one of the few objects we use exactly as they were intended — and have done for more than a century.