THIRUVANANTHAPURAM: The preliminary land acquisition proceedings of the much-touted coastal highway project connecting Thiruvananthapuram and Kasaragod have begun. As part of it, the demarcation of land using pink stones has started in a few districts. The proposed 623-km coastal highway with a width of 14 m starts from Pozhiyoor in Thiruvananthapuram district and ends at Kunjathoor near Thalapady in Kasaragod district.