Major retailers across the UK have completely sold out of solar eclipse eyewear as people travel long distances to secure a pair ahead of the most significant celestial event since the previous century.Local shops, national parks and the Royal Greenwich Society have all run out of stock prior to Wednesday's event, which is set to be the UK’s most complete solar eclipse for the next 54 years.The Royal Greenwich Observatory informed the Press Association that roughly 15,000 pairs of glasses were bought in the past month, marking a total sellout. While admission to their on-site viewing event is also fully booked, a free live stream will be broadcast on their website and YouTube channel.A convenience store in Whitechapel had to turn customers away after selling out (PA Media)High demand has left smaller stockists overwhelmed. Ali Raza, owner of a convenience store in Whitechapel, told the Press Association he had to turn away numerous hopeful buyers, adding that customers were making extensive journeys to locate the specialist glasses.Mr Raza, who owns the AM2PM store, said: “On Sunday we had people coming from Surrey, Southend-on-Sea, yesterday night a lady came from Southampton, and loads of people have come from Birmingham as well. We’re too busy.“Today I already sold 6,000 pairs. At 2.30am we had a delivery from Spain and by 9.30am we sold out everything.”Customers queue outside Am2Pm Convenience shop in Whitechapel for solar eclipse glasses and leave after being told they were temporarily sold out (PA Media)More than 90% of the sun will be obscured by the moon between 6.17pm and 8.06pm on August 12 – the most it has been blocked in the UK since the total eclipse in 1999.In the UK, Devon, Cornwall and the westernmost parts of Pembrokeshire in Wales are set to see the eclipse at its fullest, with a range of 94% to 96% of the sun obscured by the moon.Officials in Exmoor National Park, in north Devon, told the Press Association they have seen “large numbers” of people coming to see the eclipse there.The park is an international dark sky reserve and a spokesperson for the park said that they “couldn’t keep up with demand” for eclipse glasses.They said: “We got to a point where we couldn’t get any more from our supplier in time and we don’t need them again, not until 2081.In the UK, Devon, Cornwall and the westernmost parts of Pembrokeshire in Wales are set to see the eclipse at its fullest, with a range of 94% to 96% of the sun obscured by the moon (Getty/iStock)“As a national park centre, we’ve seen an increase in visitors specifically to our centre looking for those glasses and to ask us where would be the best places to go and look at it.“We advise people to go up to high moorlands or coastal headlands, or Dunkery Beacon, the highest point on Exmoor, because you get an elevated view across to the west.“We’ve sold over 300 pairs of glasses but we could’ve sold that twice over.”Exmoor will also host a now sold-out guided walk from the Hunters Inn pub where participants will watch from Highveer Point.In South Downs National Park, at least five astronomy groups are holding events, with the eclipse followed by the yearly perseid meteor shower.The Met Office said weather conditions in most of the country will be “more or less perfect” for eclipse viewing.A spokesperson told the Press Association: “With clear skies forecast across much of the UK, conditions should be more or less perfect for many to experience the partial solar eclipse.“The north and west of the country are most likely to struggle with cloud cover when viewing the eclipse on Wednesday evening, particularly across Northern Ireland and western Scotland.“The rest of Scotland and northern England may also see a good deal of high-level cloud, making skies rather hazy. The best opportunities for viewing the eclipse are likely to be south of a line from Aberystwyth to Lincoln.”A planetarium astronomer at the observatory told the Press Association that the glasses were important for viewing the eclipse safely and that sunglasses are insufficient.Imo Bell said solar telescopes – such as the ones available at the observatory’s soldout watch-along event – or holed household objects like colanders were good ways to watch the eclipse, but eclipse glasses are preferable.She said: “You can use solar eclipse glasses, which are very, very different from sunglasses – they block out so much light that you can’t see anything through them except the sun, because that’s how much light they need to block for the damaging light of the sun to be safe to view.“And if all else fails, you can project the image of the eclipse using a household item like a colander which has lots of holes in – point the colander towards the Sun with your back facing it, and in the shadow of the colander you’ll be able to see the eclipse in the holes, which is really cool.”Experts have warned that only special solar eclipse glasses that are ISO 12312-2 certified for the safest eye protection should be used to view the eclipse.Following the 1999 total solar eclipse, the Royal College of Ophthalmologists reported around 70 cases of people experiencing vision problems after watching the eclipse.Around 40% had looked at it for less than a minute.