I’m going to be studying abroad next semester over in amsterdam, and while I’m over there I will be turning 21. Now I know that the drinking age over there (among other things) is 18, so will turning 21 not be any big event? Or are there things over in Europe that a 21 year old can do that someone younger can’t?
ps: I also plan to travel to Germany and Spain, if there’s any difference…
Actually I think that you can by beer at 16 in Amsterdam. Spain is 16 also.
There are probably a lot of over-21 clubs to keep the kids out I imagine.
In the British Isles at least, 21 is celebrated as a special birthday, even though it doesn’t bring any particular legal entitlements.
re Germany I cannot think of any significance of age 21 except the following:
German criminal law allows the courts to choose to try someone who is 18 years old but not 21 years old as a juvenile. The conditions for that are: either the defendant is more immature than you’d expect of a 18-year-old, or the offence is one typically commited by juvenile delinquents. (for 14-17 year olds juvenile law always applies; under-14s are not criminally liable)
Otherwise the main age bars are: age of consent 14 years (when the other partner is under 18; 16 years otherwise); beer-drinking age 16; state voting age 16 or 18 depending on state; spirits-drinking age/car driving license age/majority age/federal voting age 18 years; eligible for federal president at 40 years.
Nitpick - there’s some vehicles you can’t get licenced to drive, including HGVs and IIRC coaches. Nor can you stand for parliament (although I think this is in the process of being changed?)
But yeah, 21 isn’t all that big an event, but like any birthday, you can make it a special occassion if you feel you deserve it 
If one was a peer one used to be able to take one’s seat in the House of Lords on one’s twenty-first birthday. One still must be twenty-one to renounce one’s peerage.
Turning 21 in Europe is quite anti-climactic. That’s what happened to me. I was on a train from Wolverhampton, England, final destination, Isola, Slovenia, on my 21st birthday, away from all my friends and pretty much everybody that I knew. Yet it was somehow perfect because it wasn’t the typical turn-21-and-puke-yer-guts-out birthday. Oh, and I also won the jackpot (150 or 200 quid) on the slot machine on the ferry from Dover to Calais.
But, no, I don’t remember any particular significance to turing 21.
That’s very much the problem. We do that too, in equally-reckless fashion, just at a different age.
One curious fact that I happened on when researching Baltic ferry connections: on Silja line ferries, the age limits for certain connections and days sometimes are as high as 23 years for people not accompanied by an adult.
Now why would that be… 
If you go to Norway you can celebrate being able to get drivers licences for heavy motorcycles and busses.
The age limit for beverages containing more than 22% alcohol by volume, is 20.
I turned 21 in St. Petersburg, and it was kind of a teachable moment for the Russians, explaining the significance of a 21st birthday in the U.S. (I think the legal drinking age may have even been 21 in Russia at the time, and it was in the middle of Gorbachev’s anti-alcohol campaign, so booze in any serious quantity was relatively hard to come by unless you had black market connections - which practically everyone did - or hard currency.)
I’m not much of a drinker anyway, but someone bought me a bottle of coffee liqueur from the hard currency store, and I had fun walking around the dorm pouring shots for the other students and getting birthday congratulations. Even if 21 isn’t normally a big deal where you are, to the OP - my hunch is you won’t have a problem finding people to celebrate with you. 