The 2015 Eschborn-Frankfurt City Loop (German: Rund um den Finanzplatz Eschborn-Frankfurt 2015) was scheduled to be the 54th edition of the Eschborn-Frankfurt City Loop semi-classic cycling race; it would have taken place on 1 May 2015. The race was cancelled the day before it was scheduled to take place because of a suspected terrorist plot similar to the Boston Marathon bombing.

The race was to have taken place on 1 May 2015 and was rated as a 1.HC event by the Union Cycliste Internationale (UCI).^[1] The planned route was 205 kilometres (127 miles) in length, starting in Eschborn and ending in Frankfurt; the course included several hills.^[2] The defending champion was Alexander Kristoff (Team Katusha).^[3] The favourites for victory included Kristoff and John Degenkolb (Team Giant–Alpecin), who had between them won Milan–San Remo, the Tour of Flanders and Paris–Roubaix.^[4]

On 30 April 2015, the day before the race was due to have taken place, local authorities announced that it had been cancelled due to "indications of a possible threat to the population".^[6] A couple, one of whom was described as a "suspected Islamic extremist", were arrested the previous day at their home in Oberursel, which is along the race route.^[6] The couple arrested were identified as Halil D., 35, a German citizen of Turkish origin, and Senay D., 34, thought to be a Turkish citizen.^[7]

Various items were found in their house, including a homemade pipe bomb, bomb-making materials, an automatic rifle, bazooka ammunition and a canister full of petrol.^[7][8][9] One of the couple had apparently bought hydrogen peroxide and alcohol at a hardware shop and had been seen exploring a forest along the race route.^[10][11] He had connections to Salafists in Frankfurt, including the group Dawa FFM.^[12][13] The German newspaper Die Welt suggested that he was involved with Al-Qaeda, specifically Al-Qaeda in the Islamic Maghreb (AQIM).^[7][8] According to German police the couple had also travelled to Spain to meet with members of Sharia4Spain.^[9] It has also been suggested that there may have been connections to Adem Yilmaz, one of those convicted as part of a bomb plot in 2007.^[14]

Security officials suggested that the couple may have been planning an attack similar to the Boston Marathon bombing in 2013.^[6] Halil D. was sentenced to two and a half years in prison in July 2016 for possession of illegal weapons and falsification of documents.^[15]