the Meditarranean Sea
FRANCE
yes
The answer you are looking for is FRANCE, but this is incorrect. Algeria was never a colony; it was annexed to France and was under French civil government (as opposed to all other French colonies were under appointed governments). Additionally, prior to French control, Algeria was a vassal and occupied territory of the Ottoman Empire, which could be seen as a colonial parent (in a non-Eurocentric model of colonialism).
It would depend on what bearing you travelled.
The English Channel. Le Manche in French.
Algeria's history is cool because of the pirates. Pirates would roam the coast and take ships from Spain, the Ottoman Empire, and France. In 1827, the Turkish dey (governor) hit the French ambassador in the face with his fly swatter while arguing about pirates and a 30 year old unpaid bill for wheat. France sent an army and placed a naval blockade. The French spent years controlling Algeria.
The English Channel.
I would think you would have to cross the channel. Go into France and then into Italy.
There aren't any trains from the US to France - it's impossible. How would a train cross the Atlantic Ocean?
The English Channel - 'Le Manche' in French.
It would take less than one second to cross the border
Technically the French did win the Algerian war. The army had reduced the guerrilla to very little, using rough techniques including the use of torture. But the political decision was made to let Algeria access to independence, considering that even if the militias were quelled, it was only for a moment and that violence would inevitably resume in the end. Other important points were that France was feeling a strong international pressure and a strong opposition from the French to let their children "go to war" in Algeria.