AN ACR FLT CREW TAXIED ONTO RWY AFTER BEING CLRED TO DO SO; BUT IT WAS AT THE WRONG TXWY.

Narrative

WE WERE CLRED FOR TKOF ON RWY 36L AT TPA AT INTXN W2. WE ASKED THE CTLR IF WE WERE INDEED AT INTXN W2. WE WERE THEN TAXIING INTO POS WHEN WE BOTH REALIZED IT WAS NOT INTXN W2. WE SUBSEQUENTLY TAXIED OFF AND RETURNED FOR TKOF UNEVENTFULLY. WE WERE TAKEN BY SURPRISE BY THE CLRNC; BECAUSE THERE WAS AN OPPOSITE TAXIING ACFT NEARBY WHICH TOOK AWAY OUR ATTN. THEN WE ASKED THE CTLR OUR EXACT LOCATION AND WE DID NOT GET A RESPONSE. I SHOULD HAVE JUST STOPPED RIGHT THERE AND THEN ASKED FOR FURTHER ASSISTANCE. I DID HAVE MY CHART OUT; BUT WITH IT BEING DARK; IT TOOK LONGER TO ORIENT MYSELF WITH THE MAP AND BY THAT TIME; THE CTLR HAD CLRED US AGAIN AND WE WERE OVER THE LINE. AS A RESULT; WE TAXIED OFF WITHOUT INCIDENT. SUPPLEMENTAL INFO FROM ACN 571938: WE WERE NOT AT THE RIGHT INTXN. TWR CONFIRMED THIS AND APOLOGIZED FOR THE MISUNDERSTANDING. CONTRIBUTING FACTORS INCLUDED DARKNESS AND AN UNFAMILIAR TAXI ROUTING DUE TO THE CONSTRUCTION. I COULD HAVE BEEN MORE ASSERTIVE WITH MY CONCERNS. I CONTEMPLATED APPLYING THE BRAKES AS WE ENTERED THE RWY; BUT DECIDED THE SIT DIDN'T WARRANT THE DANGERS OF AN ABRUPT STOP; AS WE HAD BEEN CLRED ON THE RWY.