The 2016 US presidential campaign went to some dark places at times, and its eventual winner is one of the more controversial figures to take office. So it's no surprise his inauguration will be protected by a huge security operation.
Security is a vital part of all presidential inaugurations. But for the inauguration of Donald Trump, set to take place at 5pm today, it appears to have been ramped up several notches.
The U.S. Secret Service, Washington Metropolitan Police, FBI and US Park Police are all involved in ensuring the safety of the new president and his family in an operation costing roughly $100 million.
The two sides to the operation - the visible security presence and the behind-the-scenes team - have planned for every outcome, from a gunman to a mechanised drone. Every nook and cranny has been probed and cleared, ready for today's big event.
The Coast Guard has regular patrols on the river running through the city, the Potomac, and certain bridges and streets in central Washington will be closed. Helicopters bearing the logo of US Customs will patrol the skies above America's capital, the only craft allowed to enter a vast and rigorously enforced no-fly zone.
Police have already been out in force with sniffer dogs, while security personnel are due to stand one foot apart from each other down the route the parade will take. There are large physical barriers in place, with the objective of preventing a Nice or Berlin-style truck attack.
Behind all these teams, here are tactical teams who will remain on standby, ready to react to any possible threat that makes itself known during the ceremony.
In total, there will be more than 30,000 law enforcement officers - both federal and local - and 5,000 members of the National Guard on the streets of Washington today.
In addition, a number of items have been banned for those who will be sat close to the stage on Capital Hill itself. This is comprised of the usual items, like guns and fireworks, to more obscure items - like whistles, selfie sticks, and even umbrellas, despite the 80% chance of rain in D.C. today.
That comprises the visual side of the operation, but there's another element to consider, a threat which has been put into stark relief since the end of the election: cyberattacks.
The secret service has established a center to defend against any attempts to hack the system. The agents will track any malicious codes which could potentially affect power grids, air conditioning, etc.
The services are also monitoring CCTV across every street, building, and block in the centre of the city.
Officials have stated that there are "no credible threats" to the inauguration. But it's clear that they're not taking any chances.
Washington D.C. is - for today - the most secure city on the planet.
See more about the inauguration here: