Hardest Super Mario Bros. Levels

The top ten hardest levels from 1985's genre defining game Super Mario Bros. developed by Nintendo.
The Top Ten
1 8-4

Since the timer goes by so fast it's hard to find the right path.

2 8-3
3 2-3
4 8-2

There is just so much hard things about this level.

5 8-1

I always didn't like this level

6 4-1

Just run right and you'll be fine

7 7-3
8 7-4

It is so hard to find the right path!

9 4-4
10 4-2
The Contenders
11 6-3
12 5-3
13 5-1
14 4-3
15 1-1

Why would the easiest one on here?

So hardware laugh out loud

16 7-1
17 6-4
18 1-2
19 6-1
20 5-2
21 5-4
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