Rock carvings at Chilas in Kashmir, along a major trade route in the Gilgit valley, include a pair of figures, holding what seem to be a plough and disc, wearing wide open coats similar to that of the Kushana period. They are identified as Balarama and Krishna based on the Kharoshthi inscriptions found in the area.

Source: A History of Ancient and Early Medieval India From the Stone Age to the 12th Century by Upinder Singh

Heliodorus, the Greek ambassador, describes himself as a Bhagavata—i.e., a worshipper of the god Vasudeva Krishna, and that he set up this pillar in honor of this god. The pillar is dated around 120 BCE. Nearby the remains of an ancient temple dated to the 3rd Century BCE have been found. The pillar is still standing in Besnagar, near Vidisha in Madhya Pradesh.

Source: A History of Ancient and Early Medieval India From the Stone Age to the 12th Century by Upinder Singh

Pandharpur, west of Solapur in Maharashtra, is one of the major pilgrimage sites. Vithoba or Vithala or Panduranga is worshipped in Pandharpur. Vithoba is a form of Krishna. His consort is Rukmini. Pandharpur Vari is the yatra of Varkaris the followers of saints of Maharashtra, notably, Jnaneesvar and Tukaram. Every year, they reach Pandharpur on the Ekadashi of the Ashadha month carrying Palkhis. The main Palkhis start from Alandi and Dehu and meet in Pune. Palkhis of several other saints also join the pilgrimage. They reach Pandharpur on the Ashadha Shukla 10th. The Varis have been a continuous tradition for several centuries and had united the masses.

Source: Immortal India Volume 1 by Bharatiya Vidya Bhavan.

The Lord Krishna asked his foremost disciple and devotee, Uddhava to retrieve the idol from the impending submergence of Dwaraka in the sea and install it at a spot equally holy so that He could shower His blessings on His devotees and save them from the evil effects of Kaliyuga.
Uddhava entrusted the job to Guru, the preceptor of the gods, and Vayu, the god of winds. They took possession of the idol and moved in search of a proper place. Ultimately they decided to install it near a lake full of lotuses, on one side of which there were Siva and Parvati. That is Guruvayur, the place having derived its name from Guru and Vayu who jointly installed the vigraha.

Source: Temples and Legends of Kerala by Bharatiya Bhavan

Among the most famous of the līlāsthalas near the Yamunā bank are
the forest groves where Krishna would meet the gopīs at night and dance the rās dance with each of them in a wide circle. He created a well for them when they were exhausted with the dance and too thirsty to walk to the Yamunā River. There, too, is Sevā Kunj, the very bower, so they say, where Krishna met Rādhā for lovemaking.

Source: India: A Sacred Geography by Diana Eck

The deity in Guruvayur represents the full manifestation of the Lord Mahavishnu as was revealed to Vasudeva and Devaki at the time of Krishnavatara; form of Sri Krishna endowed with the four lustrous arms carrying the conch, the discus, the mace and the lotus.

Source: Temples and Legends of Kerala by Bharatiya Bhavan

Shiva himself became a gopī to witness and enjoy the sacred rās dance of Krishna with the gopīs. He was drawn to Braj by the sound of Krishna’s flute, but was refused entry and could not cross the Yamunā until he became a woman. So Shiva bathed in the river and emerged a gopī. At Gopīshvara in the evening, Shiva is adorned by the priests with a bright sari and the silver mask of a woman wearing lipstick and eye makeup.

Source: India: A Sacred Geography by Diana Eck

A devotee named Kanakadāsa came as a pilgrim to Udupi but was unable to enter the temple because of his station in life as a shepherd. So he sang songs of devotion outside the temple, and Krishna, they say, was moved by his song. The Lord opened up a crack in the temple wall and turned 180 degrees to face west so that Kanakadāsa could have his darshan. Rather than patch up the crack, the temple authorities turned it into a window, which they dubbed Kanakadāsa’s window, through which everyone can peep in from the outside and see Lord Krishna. Today, it is customary to peek through Kanakadāsa’s silver-framed and highly ornate window before entering the temple for darshan.

Source: India: A Sacred Geography by Diana Eck

The deities are made of wood. The deities are replaced at intervals of 8, 11, 12 or 19 years, most often after 19 years. The ritual is called Nabakalebara. Four holy neem trees are identified and cut to make the famous wooden embodiments of Jagannātha Krishna. The goddess Mangalā is the guardian of the forest from which trees are cut. The priests come to the forest to seek the right tree for the new image.

Source: Immortal India Volume 1, https://www.shreejagannatha.in/nabakalebara/

Mahabalipuram is a UNESCO heritage site developed by the Pallava dynasty in the 7th and 8th centuries. Several rock cut temples, cave sanctuaries and rock carvings dot this area. The Krishna’s Butter Ball appears precariously tilted, but has defined several attempts to move it.

Source:

Shrinathji’s idol was brought to Rajasthan from Govardhana near Vrindavan to protect it from the hands of the Mughal emperor Aurangzeb who in 1665 was bent upon vandalizing the area of Vrindavan by widespread destruction of Hindu temples. For almost six months the statue stayed in Agra after which the custodians of the idol of Shrinathji left that place with the idol in search of a new location. When the wheel of the chariot carrying the Lord got stuck in the mud at a place called Sihar, the Maharana Rajsingh of Mewar saw it as a divine sign that Lord Krishna wished to settle here, and thus a temple was built at this spot and the holy township of Nathdwara grew around the temple.

Source: https://www.nathdwaratemple.org/history/shrinathjis-arrival-at-nathdwara

The Pushti Mārg tradition of Krishna worship creates yet another landscape—a linked network of havelīs, each housing a small and powerful image of Krishna, and a network of baithaks where Vallabha taught. At any one of these havelīs, the pilgrim experience brings vicarious participation as members of the extended family in the daily life of Krishna—his waking and sleeping, his caring for the cows and coming home at dusk, his swinging and his water sports. Visiting a havelī, one will catch the Lord somewhere in the daily domestic cycle and enter into that very moment.

Source: India: A Sacred Geography by Diana Eck

Tiruchambaram is associated with Kamsavadha. Here the jubilant Krishna after the killing of Kamsa is depicted in all his splendor at Tiruchambaram. Kamsa had arranged for the Kuvalayapida, the royal elephant to encounter Krishna and Balarama as they marched towards Kamsa. Krishna fought with the elephant and killed it. Therefore elephants are not taken near the temple although elephants are very much part of all other Kerala temples.
The belief is also that Krishna, after killing Kamsa went to his mother Devaki and asked for food stating that he was very hungry after the ordeal. Therefore, unlike in other temples, Naivedya is offered as soon as the temple is opened.

Source: Temples and Legends of Kerala by Bharatiya Bhavan

At the famous pilgrimage temple of Krishna Jagannātha at
Purī in Orissa, the goddess Vimalā is known as the ancient goddess of the place. Those who have studied the folk deities of Orissa and the emergence of the Krishna worship here say that this place, too, was a pitha of the Goddess long before being appropriated by Lord Krishna. Nīlāchala, on which the temple sits today, was once the domain of the goddess named Vimalā. Her shrine still is present in the sacred precincts, and she is the first to receive the prasād, the consecrated food offerings that only then become the mahāprasād, the “great grace of the Lord,” to be distributed to the worshippers.

Source: India: A Sacred Geography by Diana Eck

Bhalka Teerth is the location where the arrow of the poacher Jara hit Sri Krishna. It is about 4 or 5 kms away from Somnath.
Bhagvan Shree Krishna was resting in meditation pose under a pipal tree when the poacher misread the foot of Bhagvan Shree Krishna as a deer and hit from a distance. This divined leela of Bhagvan Shree Krishna is immortalized by a beautiful temple and an ancient pipal tree. Bhagvan Shree Krishna then walked a small distance and arrived at the holy banks of river Hiran from where he took his last journey to his Neejdham.

Source: Somnath Trust

The Parthasarathy temple in Chennai is more than 1500 years old. Here Krishna is manifest as the Charioteer of Arjuna and is depicted with a moustache and with a conch in his hand. His face is full of arrow marks, representing the arrows that he stopped during the war.

Source:

Krishna sheltered the villagers of Gokul under the GovardhanGiri for seven days and seven nights. During this entire period, he did not eat and was focused on protecting his people. Normally he is fed eight times a day. Therefore 56 items were prepared to quench his hunger after the Leela representing each of the meals he had missed.

Source: Bhoga Naivedyam by Sujata Shukla

An aging devotee used to make the trek from Dakor to Dvāraka on a regular basis to honor Krishna with tulsī leaves he had grown himself. Eventually, he became too old and lame to do so, and so he drove to Dvārakā in a cart intending to seize Krishna and take the image home with him to Dakor. Despite the security precautions of the Dvārakā Temple, Krishna was willingly kidnapped and spirited away in the cart to Dakor, where he is honored today as Rinchor.

Source: India: A Sacred Geography by Diana Eck

These coins were found in Al Khanoum in Afghanistan. Both sides of the coins bear images of male figures. What is most striking about these figures are the attributes that differentiate them. The figure on the obverse holds a miniature plough in his left hand, identifying him as Balarama, who is also known as Haladhara (wielder of the plough). In his right hand, he holds up a pestle (musala). The figure on the reverse holds a large, six-spoked wheel in his left hand against his left flank, which makes it look like a shield. This wheel (chakra) is the symbol of Vasudeva Krishna. In his right hand, he holds up something which may be a conch shell. The figure on the obverse stands between the two lines of a vertical legend in Greek, giving the name of king Agathocles. The iconographic details make the identification of the two figures certain, not ambiguous. These coins have been dated with precision to the reign of Agathocles, c. 180–170 BCE.

Source: A History of Ancient and Early Medieval India From the Stone Age to the 12th Century by Upinder Singh

This is in Vrindavan. In one story, Balarama was mocked by Yamuna for trying to imitate Krishna’s dances crudely. In a rage, Balarama drew the river with a deep furrow of his plough. An another version, Balarama got intoxicated and desired to take a bath. He ordered the river to come near him and on her refusal to come, he dragged her.

Source: Immortal India Volume 2 by Bharatiya Vidya Bhavan.