The Sycamore Gap Tree or Robin Hood Tree was a sycamore tree standing next to Hadrian's Wall near Crag Lough in Northumberland, England.

It was located in a dramatic dip in the landscape, which was created by glacial meltwater and was a popular photographic subject, described as one of the most photographed trees in the country and an emblem for the North East of England. It derived its alternative name from featuring in a prominent scene in the 1991 film Robin Hood: Prince of Thieves. The tree won the 2016 England Tree of the Year award.
Sadly, it was felled in the early morning of 28 September 2023 in what the authorities described as "an act of vandalism". The felling of the tree led to an outpouring of anger and sadness.

The tree was a sycamore (Acer pseudoplatanus). According to the National Trust, the tree was planted in the late 19th century by the previous land owner, Newcastle lawyer John Clayton (1792–1890) as a landscape feature, making it about 150 years old. Clayton was part of a wealthy family and he inherited the Roman fort of Chesters. He was a keen excavator of Hadrian's Wall, for almost 50 years, he excavated every year, enhancing the understanding of the construction of Hadrian’s Wall and became worried that it was being destroyed by people taking the dressed stone to build farmhouses and other buildings. By the time he died he owned five forts and around 20 miles of Hadrian’s Wall. By purchasing these sites he brought them under his protection.

The tree featured in a key scene near the beginning of the 1991 Kevin Costner film Robin Hood: Prince of Thieves, and has subsequently become known as the "Robin Hood Tree" - although in reality it was some 170 miles (273 km) from Sherwood Forest. It appeared in the music video for Bryan Adams' "(Everything I Do) I Do It for You", a song from the film's soundtrack; the video was shown often on the British TV series Top of the Pops.
It has also appeared in the TV crime drama Vera and in the documentary series More Tales from Northumberland with Robson Green. The site was popular among astrophotographers and stargazers. The tree escaped damage on 30 May 2003 when a helicopter filming British Isles – A Natural History crashed around 30 metres (98 ft) away, narrowly avoiding presenter Alan Titchmarsh. The four on board the aircraft were lightly injured.

In 2016, the tree was nominated for England's Tree of the Year competition. It was selected from 200 competitors for the final shortlist of 10 and won the competition with 2,542 votes out of 11,913. The prize was a £1,000 grant which was used to survey the health of the tree and to carry out work to protect its roots, which were becoming exposed due to the high volume of foot traffic passing over them. The Sycamore Gap Tree was entered in the 2017 European Tree of the Year contest in which it came 5th out of 16, polling 7,123 votes.

The tree was felled in the early morning of 28 September 2023. Locals heard nothing due to the high winds caused by Storm Agnes. The Northumberland National Park Authority said they believed it was done deliberately. The tree appeared to have been cut down with a chainsaw, at the base of its trunk, with a white line spray painted on it just below the cut. The nature of the cut and the evident sharpness of the saw led police and park rangers to conclude it had been done by someone with considerable skill.

Northumbria Police arrested a 16-year-old boy and three men in connection with the tree's felling. The force have since confirmed that no further action will be taken against the boy and one of the men; the other two men, both in their 30s, remain on bail.

The destruction of the iconic tree led to an outpouring of anger and sadness. Over the decades, the iconic tree had become the backdrop for marriage proposals, weddings and spreading the ashes of loved ones. The National Trust's regional director for the North of England, said: "The outpouring we've seen shows just how important the connection is between people and nature in its many forms, and as we consider plans for this special tree, and this very special place, we'll also look to harness that support for trees, landscapes and nature all across the country, and use the sycamore as a symbol of recovery."

On 29 September, a National Trust manager said that the stump seemed "healthy" and thought that the tree could possibly regrow in coppiced form, although he added that it would "take a few years to develop into even a small tree and around 150 to 200 years before it is anywhere close to what we have lost". Seeds were collected from the tree which are to be used to propagate new saplings.

A preliminary inspection of Hadrian's Wall by Historic England revealed "some damage". The felled tree was cut up and removed by crane for storage on National Trust property.

Coordinates 55.00356°N 2.37387°W