Summer has officially been underway since Friday, June 20, but the Fourth of July holiday is considered by many to be the official peak of the season.

Millions of Americans will be traveling across the country - and some, the globe - this summer. July and August are typically two of the biggest travel months of the year. However, according to the U.S. State Department, there are six countries on the "Do Not Travel" list this summer.

Since the start of May, when most people begin their summer travel plans, six countries have been added to the Level 4 "Do Not Travel" warning list.

According to the U.S. State Department, six countries have received the highest warning level, Level 4: Do Not Travel, since the start of May.

The six countries:

1. Russia
2. Myanmar (Burma)
3. Venezuela
4. Somalia
5. Iraq
6. Lebanon

Russia is the biggest country on the list. The U.S. State Department issued the alert back on May 8.

The U.S. State Department issued the alert for Russia for the following reasons:

1. Danger associated with the continuing war between Russia and Ukraine.
2. The risk of harassment or wrongful detention by Russian security officials.
3. The arbitrary enforcement of local laws.
4. The possibility of terrorism.

"The U.S. government has limited ability to help U.S. citizens in Russia, especially outside of Moscow. The U.S. Embassy in Moscow has reduced its staff and the Russian government has restricted travel for embassy personnel. All U.S. consulates in Russia have suspended operations, including consular services. Do not travel to Russia for any reason," the alert states.

"The U.S. Embassy in Moscow has limited ability to assist in the case of a detention of a U.S. citizen. There is no guarantee that a U.S. citizen will be afforded consular access or released before their entire prison sentence is served. The risk of wrongful detention of U.S. nationals remains high. Even if a case is determined wrongful, there is no guarantee of release."

Lebanon was added to the list on July 3, receiving a Level 4: Do Not Travel warning.

"Do Not Travel to Lebanon due to crime, terrorism, civil unrest, kidnapping, unexploded landmines, and the risk of armed conflict. Some areas, especially near the borders, have increased risk. Read the entire Travel Advisory," the alert stated.

"U.S. Embassy Beirut personnel are restricted from personal travel without advance permission. Additional travel restrictions may be imposed on U.S. personnel under Chief of Mission security responsibility, with little to no notice due to increased security issues or threats." (Mens Journal)