<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                   3-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1996             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               DEC-31-1996             MAR-31-1997             JUN-30-1997
<CASH>                                          17,657                   2,841                   3,464
<SECURITIES>                                         0                       0                       0
<RECEIVABLES>                                    1,769                   2,022                   1,876
<ALLOWANCES>                                         0                       0                       0
<INVENTORY>                                          0                       0                       0
<CURRENT-ASSETS>                                21,228                   6,853                  13,937
<PP&E>                                          37,804                  64,328                  72,978
<DEPRECIATION>                                   9,877                  11,101                  14,422
<TOTAL-ASSETS>                                  70,722                  61,438                  58,556
<CURRENT-LIABILITIES>                           32,896                  31,558                  50,562
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                            5,150                   5,150                   1,400
<PREFERRED>                                     95,215                  96,323                  99,604
<COMMON>                                         1,850                   1,958                   8,443
<OTHER-SE>                                     (94,140)               (108,900)               (122,376)
<TOTAL-LIABILITY-AND-EQUITY>                    70,722                  61,438                  76,367
<SALES>                                              0                       0                       0
<TOTAL-REVENUES>                                15,648                   9,156                  19,968
<CGS>                                                0                       0                       0
<TOTAL-COSTS>                                   56,266                  15,744                  30,657
<OTHER-EXPENSES>                                22,503                   7,021                  15,442
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                               3,260                   1,070                   2,849
<INCOME-PRETAX>                                (66,381)                (14,681)                (27,585)
<INCOME-TAX>                                         0                       0                       0
<INCOME-CONTINUING>                            (66,381)                (14,681)                (27,585)
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                   (66,381)                (14,681)                (27,585)
<EPS-PRIMARY>                                   (11.92)                  (1.98)                 (12.96)
<EPS-DILUTED>                                        0                       0                       0
        

</TABLE>