The enabling technology for supporting IP centric traffic over optical transport networks evolves as the amount of traffic grows. In this paper, we first review a recently proposed concept called light trails. Light trails can enable high speed provisioning, accommodate multigranularity traffic, support high data rates and offer a good candidate for carrying IP traffic over optical networks. Next, we focus on light trail design. We propose a two-step approach for solving the light trail design problem. The first step is called traffic matrix preprocessing, it divides single long hop paths into several shorter paths that satisfy the hop-length constraint. In the second step, the light trail design problem is formulated as an integer linear programming (ILP) optimization problem. The results obtained from our experiments show that the resulting light trail network has high wavelength utilization.