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Now in its 20th day, the government shutdown -- triggered as a result of President Donald Trump’s determination to secure funding for a border wall -- drags on. With no visible progress, services have halted, employees continue to work without pay, and the president and his opposition remain in a stalemate. So, how, if at all, could this throw a wrench in your travel plans? Here’s what you need to know.

Are airports being affected?

According to CNN, hundreds of TSA agents have been calling in sick to work. Why? As employees of the federal government, they have not been receiving a paycheck, though they are expected to be paid out post-shutdown. Despite the fewer staff numbers, the TSA says wait times have not been impacted significantly. In fact, 99.8 percent of passengers waited an average of less than 30 minutes (the standard is approximately 20 minutes), CNN reports. However, if the call outs increase, brace yourself for longer check-in and security queues. What can you do to ensure travel goes smoothly? For starters, get to the airport with plenty of time to spare. And although signing up for TSA PreCheck is not currently viable (it’s run by the government), travelers can register for Clear, which allows you to skip the line at many major airports. You can find more information on how it works and the registration process here. On a similar subject, new applicants for Global Entry must hold off for now, until the government is back up and running.

Can you still get your passport processed?

Need an expedited passport renewal ahead of your trip? Applying for a brand-new passport card? The U.S. State Department issued a statement confirming that they will “continue to offer passport services during the lapse of appropriations for the federal government.” All passport agencies are operating business as usual during the shutdown. You can also renew your documents by mail. Processing times also remain the same — four to six weeks (or two to three weeks for expedited service).

Are any national parks open?

Many national parks continue to welcome visitors, though they are highly understaffed. Services, such as restrooms, trash collection, and road maintenance, have all paused. Joshua Tree National Park was recently forced to close its campgrounds due to health issues around toilets, and Rocky Mountain National Park had to shut its roads located higher than 8,000 feet as a result of the National Park Service being unable to keep up with maintenance, CNN reports. More parks could close, if the shutdown continues, so check the National Park Service website before planning a trip.

What attractions are closed?

The Smithsonian’s 19 museums (National Air and Space Museum, National Museum of African American History and Culture, National Museum of American History, the National Zoo, and more) as well as the the National Gallery of Art are currently closed, though the Zoo will continue to care for the animals during the shutdown. However, parks like the National Mall and its surrounding monuments are still open and accessible.

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