Threats, both domestic and foreign, are driving some of the logistics of the 58th presidential inauguration as the Capitol’s top law enforcement officers prepare to secure the public and members of all three branches of government at the same time in the same place.

Recent events in France and Germany, where terrorists drove trucks into crowds of people, pose a new type of threat to consider when handling planning for the day, Senate Sergeant-at-Arms Frank Larkin said.

“We’re taking measures to protect the public against that,” Larkin said. “It’s a lot more fortified for this inauguration because of those events.”

Joined by his House counterpart, Paul Irving, Larkin told Roll Call there are also a host of issues to consider when it comes to crowd control like medical emergencies, evacuations and something no one can control — the weather.

With the event comes a massive interagency coordination effort among law enforcement in D.C., Capitol Police, plus Virginia and Maryland as well as the military, according to Irving. So far, things have gone smoothly, Irving and Larkin said, but security details are expected to evolve up to Friday.

“We are always at a heightened sense of security,” Irving said.

This is Irving’s second inauguration as House sergeant-at-arms and Larkin’s first in his Senate role. Both men previously worked in the Secret Service, where they handled the executive side of the inauguration that focused strictly on security, Irving said.

The biggest difference between how the event is handled from the perspective of Congress versus the White House largely comes down to protocol like making sure officials get where they need to be and making sure their wishes are met, Irving said.

Meanwhile, Larkin had this bit of advice for the general public: “You want a good seat — get here early.”

The inauguration starts at 11:30 a.m. on the West Front of the Capitol. Security gates will open at 6 a.m.  If it rains — don’t plan on bringing an umbrella.

That’s among a hefty list of prohibited items that also includes weapons of any kind, alcohol and selfie-sticks. Leave your pepper spray, bikes and tripods at home, too.

If you’re looking for lunch at the Capitol on Friday, service will only be available in the Longworth Cafeteria.

Expect street closures around the Capitol but look for three vehicle access points on the House side that will provide access to congressional parking garages and lots on Friday: Second and C streets Southeast, New Jersey Avenue and D Street Southeast, and South Capitol and E streets Southeast, starting at 11 p.m., Thursday.

It’s recommended that members, staff and visitors use other means of travel to the Capitol grounds rather than driving. No vehicles will be allowed to traverse the Capitol Plaza on Friday and guest parking will not be accommodated.

Tours in the Capitol Visitor Center will resume at 9 a.m. on Monday.

Access to the Capitol will be limited to only those who possess inauguration building passes starting on Thursday evening.

Public schools and libraries in D.C will be closed Friday.

On Saturday, more than 100,000 people are expected at the Women’s March on Washington — another major event that could prove taxing on security officials right after the inauguration.

The Metro system will open two hours early Saturday at 5 a.m. and run on an “enhanced” schedule to accommodate the crowd expected to march on the National Mall.