Celebrating the 200th anniversary of Arctic explorer John Rae, Orkney's community production and world premiere of Long Strides (✶ ✶ ✶) opened this year's St Magnus Festival.

No less intrepid, audiences gamely trekked to this year's novelty venue, the Orkney Riding Centre, to see the play take place in the sand of the equestrian indoor ring. After last year's opener of Carmen in the Cattle Mart, it's not hard to spot the theme artistic director Alasdair Nicolson is developing here.

On the downside it was a bit chilly; but on the upside there were cameo appearances by horse and carriage. Elaborate and colourful costumes paraded against a contrasting set of simple white drapes, with strong performances from across the cast.

An effective use of space and hazy light created a sense of historical time and dreamlike recollection. Traditional music from the band, with Douglas Montgomery on fiddle, was a particular treat, alongside catchy numbers written for the occasion by Nicolson.

Turning the heat up the following night, with a programme focused on the theme of love and midsummer, the BBC Symphony Orchestra arrived, after some travel complications, for its first visit to Orkney. They were joined by soprano Christine Brewer (✶ ✶ ✶ ✶), also new to the festival, and a singer so renowned that debuts by her must these days be a rarity.

Performing in a sports centre has its challenges, and the acoustic in this one seems particularly to take the top gloss off the upper string sound while favouring the bass. Wind intonation took a while to settle down in Mendelssohn's Midsummer Night's Dream, but Berg's Seven Early Songs hit the mark, with a detailed and colourful accompaniment from the BBCSO. Brewer's voice was full of landscapes, as she transported the audience through Berg's valleys and mountains of silver night, towards the heady scents of summer.

Tchaikovsky's Romeo And Juliet built up the romantic theme and, sure enough, delivered the thrill of a symphony orchestra at full throttle. Conductor Alexander Vedernikov seems uninterested in shaping the small phrases, leaving some lines ironed dead flat, though he comfortably steers the grand sweep of a large work.

Closing with Wagner's Prelude and Liebestod from Tristan Und Isolde, we reached the highlight of the programme. The oboe line wove beautifully through the Prelude, the first violin's voice at last clearly ringing at the top of the balance, and the bass line vibrating through your feet. At the climax of the Prelude, Vedernikov's skill in pacing the ascent became clear. After that, Brewer's voice emerged like a spectre, out of a bass pizzicato, and took us yearning through the Liebestod until she and the audience were engulfed by the final moment of supreme delight.

Emerging from yet another unexpected location, this time from behind the pulpit of St Magnus Cathedral, Emanuel Abbuhl opened the Hebrides Ensemble's late-night concert (✶ ✶ ✶ ✶) with Britten's Six Metamorphoses After Ovid, a virtuoso work for solo oboe. With his golden sound, Abbuhl drew fabulous pictures with his music. In Phaeton we were blinded by bright staccato sunlight, then lost in Niobe's lament, and enchanted by the languid vanity of Narcissus.

Alexander Janiczek (violin), Catherine Marwood (viola) and William Conway (cello) took their places on the stage for Schubert's String Trio No 1 with sweet blended sound. They later closed the concert with a comfortable and reassuringly poised Mozart's Oboe Quartet in F major, but the main event of the night was the premiere of Peter Maxwell Davies's Oboe Quartet, written specially for the ensemble.

Informed, the programme note explained, by a keen consciousness of absence from Orkney and last year's St Magnus Festival, this makes gripping, though not comfortable, listening. It opens with lyrical sadness, first of all on fragile strings, with the oboe entering much later to take over the high and expressive solo line.

With a wringing of its hands the work very gradually quickens and becomes more exercised, throwing virtuoso flourishes over it's path. Later, the strings murmur like a troubled mind, with pizzicato textures coming through like the sharp glass of madness. Jagged dance rhythms appear, but feel more like a pounding fist of angry regret. All the material is derived from an Alleluia Easter plainsong, and indeed ultimately we are led by the oboe, and driven by a variety of string textures, towards an apotheosis that feels like a moment of blinding light.

Coming rather heavily back down to earth, the Rhymes With Purple Variety Show (✶ ✶) features in this year's fringe MagFest. Despite a lively Saturday night crowd to start, there were still a few people bored enough to walk out, as the purposely shambolic MC style, card tricks and strippers flagged. An acoustic duo called the Creative Martyrs picked up the level with their macabre songs, acrobatic acts were appreciated, and vanishing doves drew a few more gasps.