The EVALSO (Enabling Virtual Access to Latin-America Southern Observatories) project, funded by the European Community (EC), aims to create a physical infrastructure to efficiently connect the Latin-America Southern Astronomical Observatories (European Southern Observatory and Observatorio Cerro Armazones) to Europe. This infrastructure will be complementary to the international infrastructure already created in the last years with the EC support. A Virtual Presence (VP) system developed by the INAF-Astronomical Observatory of Trieste (OAT) will provide the astronomers with the tools to perform and control an astronomical observation from the user's site. This will be obtained re-creating selected components of the observatory environment at a remote site in order to allow the remote astronomer to interact with the on-site operators. The main objective of this activity will be to produce a low-cost, scalable, hardware and software system to be installed, without excessive efforts, in any operative situation where a suitable connectivity can be achieved. This paper will focus on the VP sw/hw architecture and the results of the tests with remote sites.