We report on the discovery of Very High Energy ( VHE ) \gamma -ray emission from the BL Lacertae object 1ESÂ 1011+496 .
The observation was triggered by an optical outburst in March 2007 and the source was observed with the MAGIC telescope from March to May 2007 .
Observing for 18.7 hr , we find an excess of 6.2 \sigma with an integrated flux above 200 GeV of ( 1.58 \pm 0.32 ) \cdot 10 ^ { -11 } photons cm ^ { -2 } s ^ { -1 } .
The VHE \gamma -ray flux is > 40 \% higher than in March–April 2006 ( reported elsewhere ) , indicating that the VHE emission state may be related to the optical emission state .
We have also determined the redshift of 1ESÂ 1011+496 based on an optical spectrum that reveals the absorption lines of the host galaxy .
The redshift of z = 0.212 makes 1ESÂ 1011+496 the most distant source observed to emit VHE \gamma -rays to date .