A tension-based tension leg platform (TBTLP) for use in ultra deepwater applications to support dry-tree oil and gas production utilizes a tension base or artificial seabed that simplifies tendon design at deepwater locations in harsh environment and has a truss pontoon structure that reduces vertical and horizontal wave loadings. The platform may include a riser support tower that makes production risers feasible in 8,000 ft water depths without riser pretension to the hull and reduces or eliminates vortex induced vibration problems.