The paper deals with the development of The Danish Test Site for Wave Energy (DanWEC test site).The wave energy sector is at a development stage where real-sea testing is imperative. Dedicated test sites for development of wave energy converters are being established in many European countries.The DanWEC test site is situated on the North-West coast of the Danish peninsula Jutland near Hanstholm facing the North Sea. DanWEC has for many years been the center for development of the Danish wave energy sector.DanWEC has a well developed methodology for testing. This methodoly for testing, assessing and evaluating the different devises being tested will be presented. Objectives of real sea trials are typically 'proof of concept tests', but also more detailed test for increasing power production, decreasing costs or extending life time of components or the complete device.Some of the most important parameters needed for structured testing are the environmental conditions like currents, wave and wind. The wave data acquisition network of the test site comprises three wave buoys. The first buoy was installed in 1998 and has provided almost 20 years of uni-directional data. The two newer directional buoys were installed in 2015, and have refined the data knowledge including insight on the directionality of the waves. The data has now been used to set-up a numerical model for current, waves and wind based on the MIKE 21SW software. The numerical model is able to give forecasts for current, waves and wind up to 5 days ahead. The forecast updates a range of parameters twice every day in order to deliver data for O&M operations. A more extensive description of the model will be presented in the paper. Futher results of a 30 years hind cast study will present annual and seasonal variations in the wave climate at the test site.