IP based geolocation is a widely used geolocation technique because of its ability to geolocate the hosts where GPS or other techniques become ineffective or unavailable. Measurement-based geolocation techniques utilize landmarks to make end-to-end delay measurements and compute the host location based on delay to distance mappings. Fewer landmarks and/or inaccurate delay to distance mapping leads to large error margins. In this research an Adaptive-IP-Geolocation (AIG) technique is proposed. AIG is based on PingER and PerfSonar worldwide deployments. Based on the analysis of PingER data, AIG uses two tier approach where tier one landmarks identify the region of a target host. This is followed by geolocation of the target host using regional landmarks only. A variable alpha is introduced for delay to distance conversion. Results show that AIG outperforms previous techniques with the error margin reduced to 25 km or less for the majority of the hosts in the tested region. Show Partial Abstract