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tokens: as follows. We describe the observations, archival data we used, and data reduction in Section 2 . We present the results of our analysis of jet structure, opacity, collimation, and acceleration in Section 3 . The results are discussed in Section 4 . We summarize our findings and conclude in Section 5 . 2. Observations and Data Reduction 2.1. Multifrequency VLBA Observation We observed NGC 315 with the VLBA on 2020 January 05 at frequencies of 1.548, 2.284, 4.980, 8.416, 15.256, 22.220, and 43.120 GHz. All 10 VLBA stations successfully participated in the observation. The data were recorded in both right- and left-hand circular polarizations with two-bit quantization in eight baseband channels (also often called intermediate frequencies [IFs]), using the polyphase filterbank (PFB) observing system, at a recording rate of 2 Gbps, yielding a total bandwidth of 256 MHz for each polarization. The total observation time is 12 hr. The on-source time on our target is ≈40 minutes at 1.5–8.4 GHz and ≈50, 80, and 100 minutes at 15.3, 22.2, and 43.1 GHz, respectively. The weather conditions were good, and no major technical issue occurred during the observation at all stations. We summarize the basic properties of our data in Table 1 . Table 1 Multifrequency Observations and Data of NGC 315 Note. (a) Major axis, minor axis, and position angle of the synthesized beam under the natural weighting of the data. (b) Map peak intensity in units of Jy per beam. (c) Image rms noise measured in the off-source regions in units of mJy per beam. I rms is relatively high at 2.3 GHz owing to (i) the signals in some IFs being blocked by the filters installed in many stations and (ii) severe radio frequency interference in this band. (d) FWHM of the core modelfit elliptical Gaussian component along the perpendicular direction to the jet axis. (e) FWHM of the core JMFIT elliptical Gaussian component along the perpendicular direction to the jet axis. Statistical and systematic errors in the fitted core sizes in (d) and (e) are noted. 1 Participating stations: the VLBA (except Maunakea station), the Effelsberg 100 m station, the Green Bank Telescope, and the phased-up VLA. We performed a standard data reduction with the NRAO’s Astronomical Image Processing System (AIPS; Greisen 2003 , see, e.g., Section C in the AIPS cookbook 12 12 http://www.aips.nrao.edu/CookHTML/CookBook.html ). We updated the Earth Orientation Parameters using more accurate parameters that are available after the data correlation, taken from NASA CDDIS. We corrected the dispersive delays caused by the ionosphere by using the GPS models of the electron content in the ionosphere using the procedure VLBATECR in AIPS. The sampler voltage offsets were corrected by using the autocorrelation spectra. We removed the instrumental delay residuals and phase offsets between IFs by performing a “manual phase-cal” using a scan of bright calibrators such as 0133+476, 3C 84, and BL Lac. The bandpass shapes of the