The oldest mud baths in Ukraine is located in the north-eastern part of Odessa, 13 km from the city center at the foot of Zhevakhova Mountain on the right bank of the Kuyalnik estuary. Unique in its healing properties, the mud resort Kuyalnik has been helping people improve their health for many decades. Nature has not been stingy, generously gifting this land with a dry and warm climate, a large number of sunny days a year, healing mud (peloids) and brine, mineral water springs, creating ideal conditions for healing many diseases and resting people here. According to some researchers, the name of the resort is associated with the high concentration of salt in the water of the estuary. From the Turkic "kuyalnik" - thick. Salt was mined here from time immemorial until 1932. Other scientists believe that the name of the resort is not of Turkic, but of Slavic origin; the ancient Slavs called the kuyalnik a boat dock, piers. Historians claim that there was an ancient settlement on Zhevakhova Mountain, and a large pier on the shore of the reservoir. Salt was not the only thing mined in the estuary. In G. Boplan's book "Description of Ukraine" (1660), it is indicated that the Kuyalnitsky estuary was abundant in fish, there were carps and pikes of "incredible size". To catch them, "whole caravans from places 50 miles or more away" came. In the past, the Kuyalnitsky estuary, like the Khadzhibeysky, was a bay of the Black Sea. It is believed that on the shore of the estuary there was one of the piers of the busy trade route of Kyiv along the Ros - Southern Bug - Kodyma - Kuyalnik rivers to the shores of Bulgaria and Greece. This route had the advantage that boats loaded with goods went to the Black Sea, bypassing the Dnieper rapids. Even today, numerous fragments of various dishes from the 4th-5th centuries BC are found on the banks of the estuary. And on the territory of the village of Kuyalnik, already in Soviet times, the remains of a settlement were discovered, the foundation of which dates back to the beginning of the 1st millennium BC.

On the site of the Khadzhibey and Kuyalnik estuaries there were mouths of rivers - Maly and Bolshoy Kuyalnik. Having “captured” these mouths, the Black Sea turned them into its bays. Then the deposition of river and sea sand formed Peresyp, and the bays became estuaries. The Kuyalnik estuary separated from the sea much later than the Khadzhibey one, as evidenced by the narrower Peresyp.

The salty waters of the estuary, having “broke away” from the sea, compacted into brine - a saturated saline solution. Another unique feature of the estuary is that layers of silt peloids containing many different mineral particles and organic substances lay on the bottom. Complex chemical processes and the “work” of various bacteria have given peloids invaluable medicinal properties.

According to E.M. Brusilovsky (“Odessa Estuaries and Their Healing Remedies”, 1914), in October 1833, on the orders of the head of the region, Count Vorontsov, the first estuary hospital was built, which was officially called “The Hospital of Dirty and Sandy Estuary Baths”. And although the resort was very primitive, consisting of “warm wooden greenhouses and a cold bathhouse”, its fame soon spread throughout the country and beyond. The Odessa Construction Committee ordered the construction of a new two-story house with all the necessary equipment for medical purposes. The construction of this second health resort was completed in 1842 and leased to the head of the baths at the Kuyalnik estuary, divisional doctor Erast Stepanovich Andreevsky, who understood that the time had come to build a health resort on the shore of the Kuyalnik estuary, and immediately got down to business, becoming the first organizer of the resort business on Kuyalnik. This was the beginning of the Kuyalnik resort.

During the Crimean War of 1853-1856, the resort ceased to exist. Odessa was preparing to repel the Anglo-French-Turkish landing, an artillery battery was installed on the shore of the estuary. And after the war, it was leased for 10 years to an enterprising manufacturer who organized industrial salt mining here.

The famous Russian surgeon Nikolai Ivanovich Pirogov visited Kuyalnik several times during his stay in Odessa in 1856-1858. He outlined his thoughts on the treatment of the wounded suffering from purulent, poorly healing wounds in his book “The Principles of General Military Field Surgery”. N.I. Pirogov’s advice was only truly heard more than 60 years later – during the First World War, a special military hospital was opened in Kuyalnik. The Odessa medical community was seriously alarmed by the responsible position of the resort, and under its pressure, in 1865 the Odessa City Duma adopted the famous decree “To return the Kuyalnik bathing establishment to its former purpose”. Literally in a couple of years, the estuary was overgrown with summer houses, boarding houses, and hospitals. And after the commissioning of the Kuyalnik-Odessa railway line in 1868, a real resort “fever” began here. Despite the “lack of amenities,” patients from abroad began to travel to Kuyalnik, where they heard about the unique properties of Odessa’s therapeutic mud.

About 21 thousand mud treatments and 44 thousand baths in the estuary water were administered in Kuyalnik. With the commissioning of a new capital mud baths in 1892, built according to the design of the architect S.V. Tulunsky, it became possible to conduct spa treatment all year round. This building has survived to this day.

Up until the revolution, Kuyalnik could only be called a resort, in the current sense of the word. The housing situation in Kuyalnik was especially bad. While wealthy people had the opportunity to stay in city hotels or rent dachas, the poor who flocked here for treatment were in a difficult situation.

By 1914, the first sanatorium building was built for the population on the territory of Kuyalnik, then a building for officers, as well as a ceremonial entrance to the resort. In the 1920s, thanks to scientists, the method of servicing patients was changed and improved, an application method of mud therapy was introduced, allowing to increase the capacity of the mud baths. During the war of 1941-1945, Kuyalnik suffered greatly. Having blown up the protective dam, the Nazis flooded a park of 18 hectares, disabled the mud baths, and destroyed almost all the sanatoriums built during the five-year plans. After the war, in 1947, the resort was reopened. New effective methods of treatment were introduced. Patients were treated mainly on a course basis. In the 1970s, construction of modern dormitory buildings began, which are now located on the territory of the resort. Years of construction 1976 1981, 1986.

For the development of the first resort of Odessa, a lot was done by natural scientists and doctors of the city. The healing properties of peloids were studied, their composition, the mechanism of action of mud procedures on the patient's body, methods of heating therapeutic mud, the chemical composition of estuary brine, sea water were studied. A scientific base was created for mud-mud treatment.

Since the 20s of the XX century, active resort construction began. Mud economy, the number of sanatorium places increased, the resort began to function all year round. A connection was established between the resort and medical and preventive institutions that referred patients for spa treatment. A resort polyclinic was created, sanatoriums became the main medical and preventive institutions at the resort. Scientists in spa treatment are developing methods of combined mud therapy, substantiating the feasibility of using and introducing into practice mud applications of so-called winter mud therapy.

It is necessary to mention the founders of the doctrine of estuaries and peloids - A.A. Verigo, Yu.A. Bardakh, E.M. Brusnilovsky, as well as the study of the physical and chemical properties of therapeutic mud.

The development of medical science at the resort was facilitated by the active work of the Odessa Research Institute of Balneology, which was created in 1927.

Scientists were engaged in the development of new methods and techniques of mud therapy. On the initiative of the famous specialist in mud therapy M.S. Belenky, the release of diluted mud baths chatterboxes was resumed in Kuyalnik for the treatment of patients with rheumatic diseases, diseases of the peripheral nervous system. Scientists in Odessa balneology proposed to revive the use of mud applications at the resort. A number of fundamental studies have shown that mud applications are as effective as mud baths, but at the same time significantly less tiring for patients and much more economical. For the first time in the practice of mud therapy, mud applications in the open air were used in the summer.

The founder and first head of the arthrological clinic, first in Kuyalnik, and then in the Odessa Research Institute of Balneology, was Professor E.M. Brusilovsky, an arthrologist, the founder of the Odessa school of balneologists-arthologists. He proposed a classification of joint diseases and the developed method of peloidotherapy and a combination of the latter with other physiotherapeutic factors.

Today, a comprehensive study of peloids, brine and mineral waters of the Kuyalnik deposit, research on monitoring their quality is carried out in Odessa at the Ukrainian State Center for Standardization and Quality Control of Natural and Preformed Products.

According to the results of the medical and biological assessment of the peloids of the southern part of the Kuyalnik estuary, conducted by the institute, it was established that they can be used for external use only directly at the Kuyalnik resort for the following main medical indications: diseases of the musculoskeletal system, nervous system, gynecological diseases, today at the Kuyalnik resort there are diseases of the male genital organs and digestive organs (medical (balneological) conclusion of 10.12. 2008 No. 224).

The resort is also famous for its sodium chloride mineral water. The employees of the gastroenterology department of the Odessa Research Institute of Balneology have proven the effectiveness and developed differentiated indications for the use of mineral waters of the Kuyalnik deposit for diseases of the digestive organs.

The Institute has completed work on the medical and biological assessment of the mineral waters of the Paleogene aquifer of the Kuyalnitskoye mineral water deposit (well No. 16) when used by the resort institution of the N.I. Pirogov Clinical Sanatorium (medical (balneological) conclusion of 10.03. 2009 No. 241). It was established that the waters can be used as natural medicinal mineral waters for external use for medical reasons.

The underground waters of well No. 10 of the N.I. Pirogov Clinical Sanatorium are used as medicinal waters, the indications for which, according to the medical (balneological) conclusion of 10.03. 2009, No. 242.

Today, the Kuyalnik resort operates the DP "Clinical Sanatorium named after N.I. Pirogov" PJSC "Ukrprofzdravnitsa", and has all the necessary conditions for a full-fledged rest and treatment. The influx of vacationers to the sanatorium during the season is huge - not only Odessans are recovering, but also patients from various regions of Ukraine, the CIS countries, as well as from Syria, Israel, Germany, Kuwait and other countries. Sanatorium rehabilitation is one of the most accessible stages of restorative treatment, which determines the relevance of continuous improvement of the health resort. Therefore, it is necessary to use the accumulated practical experience to further improve the effectiveness of restorative treatment of patients at the Kuyalnik resort, develop an effective treatment strategy and determine priority areas of research.

The issue of restoration and preservation of natural healing resources of the Kuyalnik resort has recently received close attention from the state. A decision was also made to create a state program for the preservation of the estuaries of the northwestern Black Sea region. In turn, the Odessa Regional Council approved a regional program for the preservation and restoration of water resources in the Kuyalnik estuary basin.