Mokoia Island is located in Lake Rotorua in New Zealand. It has an area of 1.35 square kilometres. The island is a rhyolite lava dome, rising to 180 metres above the lake surface. It was formed after the Rotorua caldera collapsed and rhyolitic magma was pushed through the cracks. One of the cracks was below where Mokoia island is today. The foreshores of the island have geothermal springs with hot spring water forming the Hinemoa pool, known to locals as Waikimihia. It also has very rich volcanic soil, which was why the local Māori grew kumara on it. it was also a very good strategic location, which was why it was often fought over.
Mokoia Island is privately owned by local Māori iwi, who run it in conjunction with the New Zealand Department of Conservation. It is a bird sanctuary and access is limited to tour parties only. It is home to several rare species, including the kokako, the kiwi, and a breeding population of the endangered saddleback.
Hinemoa and Tutanekai
The island is sacred to Māori of the Te Arawa iwi, and is the location of one of the most famous legends of New Zealand, that of Hinemoa and Tutanekai, which has parallels with the classical Greek tale of Hero and Leander, and with Shakespeare's Romeo and Juliet, but with a happier ending.
According to legend, the two lovers were forbidden to marry, and Hinemoa's father Umukaria, a chief from the shores of the lake, ordered that she not be allowed to travel by canoe to Tutanekai's tribal village on the island. Hinemoa decided to swim 3.2 kilometres across the lake to the island, guided by the sound of Tutanekai's flute-playing. For flotation she wrapped rushes (a type of reed) around her and swam her way to the island. 
The legend was filmed several times in early New Zealand films:
- Hinemoa (1913) by Gaston Méliès
- Hinemoa (1914) by George Tarr
- The Romance of Hine-moa (1927) by Gustav Pauli
Story of Tutanekai and Hinemoa: Hinemoa was the daughter of a great chief who lived at Owhata, on the shore of Lake Rotorua. She was very beautiful, and because of her beauty and her high rank, many young men desired her as a wife. One of these was Tutanekai, but he knew that though he was of good birth, his rank was not high enough for Hinemoa's father to accept him as his daughter's suitor.
So for a long time Tutanekai hid his love. He saw Hinemoa only when there were great meetings of the tribe, for his home was far across the water, at Mokoia Island in the middle of the lake. When the people gathered together he would content himself with gazing at Hinemoa from a distance, and yet it seemed to him that sometimes she would return his looks. But he thought to himself, ‘There are many other young men more worthy than I of winning Hinemoa's heart. If I approach her to declare my love, perhaps she will be displeased.’
Now Hinemoa did love Tutanekai, but she too hid her love, thinking, ‘If I send a message to Tutanekai, perhaps he will not care for me’.
At last, after many meetings at which their eyes only had spoken, Tutanekai sent a messenger to Hinemoa, and when she had heard him, Hinemoa cried joyfully, ‘Have we each then loved alike?’ Then Tutanekai asked Hinemoa to leave her home and come to him, and to this she agreed.
‘At night’, he said, ‘when you hear the sound of a flute across the water, it is I; come in your canoe’.
Every night Tutanekai sat on a high hill and played his flute, and the wind bore his music far across the lake to Hinemoa's home. But Hinemoa did not come. Her people had suspected her intention, and they had pulled all the canoes high up on the shore. Every night Hinemoa heard the sound of her lover's flute, and wept because she could not go to him. Then she thought at last, ‘Would it be possible to swim?’ She looked at the wide water and her heart failed her; but then she heard the flute again and knew that she must go.
Then Hinemoa took six hollow gourds and fastened them to her body to buoy her up, three to either side. The night was dark, and the great lake was cold. Her heart was beating with terror, but the flute played on. She stood on a rock by the shore and there she left her garments. Then she entered the water and swam toward the music. After a time she was exhausted, and drifted with the current of the lake, supported by her gourds. Then she recovered her strength and swam on. In the darkness she could see no land, and had only Tutanekai's flute to guide her; and led by that sweet sound she came at last to the island.
At the place where she landed there is a hot pool, and Hinemoa went into this to warm herself, for she was trembling with cold; she trembled as well with modesty, at the thought of meeting Tutanekai.
Just then Tutanekai happened to feel thirsty, and said to his servant, ‘Go, fetch me some water’. So the servant went and filled a gourd with water close to where Hinemoa was sitting. In the darkness she disguised her voice and pretended to be a man, calling out gruffly, ‘For whom is this water?’
The servant answered, ‘It is for Tutanekai’. Then Hinemoa said, ‘Give it to me’. So he gave her the gourd, and when she had drunk from it she broke it in pieces. Then the servant said, ‘What business had you to break the gourd of Tutanekai?’ But Hinemoa did not answer.
The servant went back, and Tutanekai asked him, ‘Where is the water I told you to bring?’
He answered, ‘Your gourd has been broken’.
‘Who broke it?’
‘The man who is in the pool’.
‘Go back again then, and fetch me some water’.
The servant took a second gourd and returned to the pool. Again Hinemoa called to him, ‘For whom is this water?’ Again the servant replied, For Tutanekai’.
‘Give it to me’. And she took the gourd and broke it in pieces as she had the other.
When the servant went back to Tutanekai, and Tutanekai heard that the man had broken a gourd a second time, he was wild with rage.
‘Who is this fellow?’ he said.
‘How can I tell?’ said the servant. ‘He's a stranger’.
‘Didn't he know the water was for me? How did the rascal dare to break my gourds? I am furious at his insolence’.
Then Tutanekai caught up his spear and went to the side of the pool, and called out, ‘Where is the fellow who has broken my gourds?’ Hinemoa knew by his voice that this was Tutanekai, and she hid under the overhanging rocks at the edge of the pool. She did this from shyness, so that Tutanekai might not find her at once, but only after trouble and careful searching. Then Tutanekai went feeling along the edges of the lake, seeking everywhere, while she lay hidden, looking out and wondering when he would find her.
At last he caught hold of a hand, and said, ‘Ho ho, what's this?’ And Hinemoa answered, ‘It is I, Tutanekai’. And he said, ‘But who are you? Who's I?’ Then she said more loudly, ‘It is I, it is Hinemoa’. Then he said, ‘Ah, can this really be? Come then to my house’. And she answered, ‘Yes’, and rose up from the water as beautiful as the wild white hawk, and stepped upon the side of the pool as graceful as the shy white crane; and he threw his cloak about her, and took her to his house, and thenceforth, according to the customs of those days, they were man and wife.
In the morning, when all the people in the village came out of their houses to get their breakfast. Tutanekai remained inside. His father said, ‘This is the first morning Tutanekai has slept in like this; perhaps he isn't well’. He sent a servant to see, and the servant slid back the wooden window and peered inside. Then to his astonishment he saw in the room not two, but four feet. He ran back to his master and told him this. Then Tutanekai's father said, ‘Who is his companion? Go quickly and see’. So the servant went back, and saw that it was Hinemoa.
Then he shouted out in amazement, ‘Oh, here's Hinemoa, here's Hinemoa in the house of Tutanekai!’, and all the village heard him, and there arose cries on every side, ‘Oh, here's Hinemoa, here's Hinemoa in the house of Tutanekai!’ Then some of the people said, ‘It can't be true, Tutanekai can't have won Hinemoa’.
But then Tutanekai came out of his house, and behind him came Hinemoa, and everyone saw that it was true.
All this was a long time ago. The descendants of Hinemoa and Tutanekai are living at Rotorua to this day, and still they tell the story of how the beautiful Hinemoa swam across the great lake to her lover.
The traditional Maori love song Pokarekare Ana is widely known and is based on the story of Tutanekai and Hinemoa. The lyrics tell of Hinemoa's crossing the lake to reach Tutanekai.