The town of Lahti, 100 kilometres north-east of Helsinki, has been home to a Sibelius Festival since 2000, the year in which its magnificent lake-side concert hall opened. In 2015, to celebrate the 150th anniversary of the composer’s birth, the festival has been extended from three days to a week with six orchestral concerts shared between three orchestras, three chamber music concerts, two piano recitals and a song recital.

An international band of enthusiasts congregated in brilliant late summer sunshine at the Sibelius Hall to enjoy the opening concert of the week, given by the Helsinki Symphony Orchestra conducted by Leif Segerstam. Inside the hall, thoughts of the sunlight sparkling on Lake Vesijärvi a few metres away were quickly replaced with the spirit of the dark Finnish woods, for the first piece to be played was Tapiola. In Finnish mythology Tapio is the god of the forest and Tapiola is his domain. This tone poem is the composer’s last major work and is an intense and dark piece, developing themes with symphonic rigour while conjuring up impressions of nature with masterly orchestral effects. In Segerstam’s hands, the large orchestra made the wind howl and the air freeze. It was clear from the start that Sibelius’ music was the lifeblood of this orchestra and conductor.

We remained in the world of Finnish mythology for the rest of the evening, and in particular works inspired by the Kalevala, the Finnish national epic which was put together from folk sources by Elias Lönrott and published in 1835, with a revised version appearing in 1849. The Kalevala established Finnish as a literary language and proved highly influential not only on Sibelius but also on visual artists. As a result of Sibelius’ music, the Kalevala has become known around the world.

Luonnotar, one of Sibelius’ most beautiful and unusual works, was the second piece in the concertThis “tone poem for soprano and orchestra” tells the Finnish creation myth in verses from the Kalevala. They were sung by Finnish soprano Anu Komsi. To say that her voice soared over the orchestra when necessary and rose out if it gradually or suddenly depending on the requirements of the music and the text, although true, would be to miss the essence of the performance. Ms Komsi seemed to become the spirit of nature of the title. Through her voice, and indeed her body language, she had the audience transfixed as she led them though the story. The large orchestra (including two harps and two timpanists) gave fine support but the focus was always on the singer. This was a truly magnificent performance.

During the interval, we enjoyed the low sun glowing over the lake and then returned to the world of Finnish legend and musical storytelling for the four tone poems of the Lemmkäinen Suite. This came much earlier in Sibelius’ output than the pieces heard in the first half of the concert. In the 1890s, Sibelius had planned a Wagnerian opera on stories from the Kalevala. In the end the opera came to nothing, but much of the music already composed was transferred to the Lemminkäinen Legends which were first performed in 1896 but were revised later. They are often played separately, especially The Swan of Tuonela, one of the composer’s most frequently performed works, but when played together they form a powerful and satisfying whole.

Lemminkäinen and the Maidens of the Island came first with the orchestra vividly depicting the escapades of the hero. String and woodwind solos emerged from a large orchestra to point details of the tale and create a variety of moods. Two mainly slow movements followed, played in the reverse of the usual order. Lemminkäinen in Tuonela depicted the hero’s journey to the Finnish hell. The dark and dangerous surroundings were conjured up with prominent basses and cellos; throughout the movement the atmosphere was agitated, tense and dramatic. It ended quite abruptly, and was followed by a depiction of the black swan floating on the river in The Swan of Tuonela. In contrast to the preceding movement this was calm and unhurried though no less dark. The famous cor anglais solo was played beautifully by Antti Turtiainen. With the concluding Lemminkäinen’s Return we were back in the world of the action hero, the music brighter and faster than that of the two central movements and reaching a glorious conclusion as Lemminkäinen finally reached home.

As an encore we were treated to some much brighter Sibelius: the alla marcia from the Karelia Suite. This was a memorable concert. Conductor and orchestra (and in Luonnotar the soloist) were as one, spellbinding the audience as they led us through episodes Finnish mythology as vividly translated into music by Sibelius. The 15th Lahti Sibelius Festival could not have had a more promising start.