you can simply go to any exchange that has DOGE/BTC pair and can get btc easily. ex. yobit, poloniex, cryptopia
I've exchanged around 45k doge to btc in yobit. with no issues.
Thanks about advice of the Poloniex... I exchanged all my rest DOGEs and am satisfied now. I lost maybe half, but still am on the 4x more value for what I bought them before 4 years. Thank you all guys. An firstly I tried to use bter before 4 days but wait a long time for ID verification which is still in the progress. Poloniex work flawlesly.
BTW there is a LOT of scammers I got maybe 10 PM which shit like "send me doges i need it to pay rent" or "sent me doges i sent you already bitcoins look to the chain" and other "send me doges or I will report you as scammer" I may only smile. Once this peoples know someone got you, they simply trying to get his own piece of cake too hahaaha

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Thank you all.
and to SCAMers: dont sent me PMs and go to hell I will not reply, you wasting you fucking doggy anus styled life. Die in hell.